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❓Given the line x-2y-1=0 and the circle (x-1)^{2}+y^{2}=1 intersect at points A and B, then |AB|= ______.
💡Alright, so I've got this problem here where I need to find the distance between points A and B where the line x - 2y - 1 = 0 intersects the circle (x - 1)^2 + y^2 = 1. Hmm, okay, let me break this down step by step.First, I remember that to find the points of intersection between a line and a circle, I can solve their equations simultaneously. That means I'll need to substitute one equation into the other to eliminate one variable and solve for the other. Let me see... The line equation is x - 2y - 1 = 0, so maybe I can solve for x in terms of y or vice versa.Let me solve for x because it looks straightforward. If I rearrange the line equation, I get x = 2y + 1. Okay, so x is expressed in terms of y. Now, I can substitute this expression for x into the circle equation. The circle equation is (x - 1)^2 + y^2 = 1. Substituting x = 2y + 1 into this should give me an equation in terms of y only.So, substituting, we have ( (2y + 1) - 1 )^2 + y^2 = 1. Simplifying inside the parentheses first: (2y + 1 - 1) becomes 2y. So now the equation is (2y)^2 + y^2 = 1. Calculating (2y)^2 gives 4y^2, so the equation becomes 4y^2 + y^2 = 1. Combining like terms, that's 5y^2 = 1.To solve for y, I divide both sides by 5, getting y^2 = 1/5. Taking the square root of both sides, y = ±√(1/5). Simplifying √(1/5), that's the same as √5 / 5. So, y = √5 / 5 and y = -√5 / 5. Okay, so we have two y-values where the line intersects the circle.Now, I need to find the corresponding x-values for each y. Remember, x = 2y + 1. So, plugging in y = √5 / 5, we get x = 2*(√5 / 5) + 1. That simplifies to (2√5)/5 + 1. To combine these, I can write 1 as 5/5, so x = (2√5 + 5)/5. Similarly, for y = -√5 / 5, x = 2*(-√5 / 5) + 1 = (-2√5)/5 + 1 = (-2√5 + 5)/5.So, the two points of intersection, A and B, are ((2√5 + 5)/5, √5 / 5) and ((-2√5 + 5)/5, -√5 / 5). Now, I need to find the distance between these two points, |AB|.To find the distance between two points (x1, y1) and (x2, y2), I can use the distance formula: √[(x2 - x1)^2 + (y2 - y1)^2]. Let's assign point A as ((2√5 + 5)/5, √5 / 5) and point B as ((-2√5 + 5)/5, -√5 / 5).Calculating the differences first: For the x-coordinates: x2 - x1 = [(-2√5 + 5)/5] - [(2√5 + 5)/5] = (-2√5 + 5 - 2√5 - 5)/5 = (-4√5)/5.For the y-coordinates: y2 - y1 = (-√5 / 5) - (√5 / 5) = (-√5 - √5)/5 = (-2√5)/5.Now, squaring these differences:(x2 - x1)^2 = [(-4√5)/5]^2 = (16*5)/25 = 80/25 = 16/5.(y2 - y1)^2 = [(-2√5)/5]^2 = (4*5)/25 = 20/25 = 4/5.Adding these together: 16/5 + 4/5 = 20/5 = 4.Taking the square root of 4 gives 2. So, the distance |AB| is 2 units.Wait a second, that seems straightforward, but let me double-check if there's another way to approach this problem, maybe using the properties of circles and lines.I recall that the length of the chord (which is AB in this case) can be found using the formula: |AB| = 2√(r^2 - d^2), where r is the radius of the circle and d is the distance from the center of the circle to the line.Given the circle equation (x - 1)^2 + y^2 = 1, the center is at (1, 0) and the radius r is 1.Now, let's find the distance d from the center (1, 0) to the line x - 2y - 1 = 0. The formula for the distance from a point (x0, y0) to the line Ax + By + C = 0 is |Ax0 + By0 + C| / √(A^2 + B^2).Here, A = 1, B = -2, C = -1. Plugging in the center coordinates (1, 0):d = |1*1 + (-2)*0 - 1| / √(1^2 + (-2)^2) = |1 - 0 - 1| / √(1 + 4) = |0| / √5 = 0.So, the distance d is 0, which means the line passes through the center of the circle. Therefore, the chord AB is actually the diameter of the circle. Since the radius is 1, the diameter is 2*1 = 2. So, |AB| = 2.That confirms my earlier calculation. So, both methods lead to the same answer, which is reassuring.I think I've covered all the steps thoroughly. I first found the points of intersection by solving the equations, then used the distance formula. Then, as a check, I used the chord length formula by calculating the distance from the center to the line, realizing that since the distance is zero, the chord is the diameter. Both methods gave me the same result, so I'm confident that |AB| is indeed 2.**Final Answer**The length of segment AB is boxed{2}.
❓Determine the largest of the following quantities (write A, B, or C):[ A. frac{2020}{2019}+frac{2020}{2021} qquad B. frac{2021}{2022}+frac{2023}{2022} qquad C. frac{2022}{2021}+frac{2022}{2023} ]
💡Okay, so I have this problem where I need to figure out which of the three quantities A, B, or C is the largest. The quantities are given as:A. 2020/2019 + 2020/2021B. 2021/2022 + 2023/2022C. 2022/2021 + 2022/2023Hmm, let me think about how to approach this. I remember that when comparing fractions, sometimes it's helpful to find a common denominator or to approximate the values. Since all these fractions are close to 1, maybe I can approximate them or find a way to compare them more easily.Let me write down each expression again to see if I can spot a pattern or a way to simplify:A: 2020/2019 + 2020/2021B: 2021/2022 + 2023/2022C: 2022/2021 + 2022/2023Looking at each one, I notice that in A, both fractions have 2020 in the numerator, but the denominators are 2019 and 2021, which are one less and one more than 2020. Similarly, in C, both fractions have 2022 in the numerator, with denominators 2021 and 2023. In B, the numerators are 2021 and 2023, and the denominator is 2022 for both fractions.Maybe I can express each of these in terms of a variable to make it easier. Let me try that.For A, let me set n = 2020. Then, A becomes:n/(n-1) + n/(n+1)Similarly, for C, let me set n = 2022. Then, C becomes:n/(n-1) + n/(n+1)Wait, that's interesting. Both A and C have the same structure, just with different values of n. For A, n is 2020, and for C, n is 2022.What about B? Let me see. For B, the numerators are 2021 and 2023, and the denominator is 2022. So, if I set n = 2022, then B can be written as:(n-1)/n + (n+1)/nWhich simplifies to:(n-1 + n + 1)/n = (2n)/n = 2Oh, so B is exactly 2. That's straightforward.Now, for A and C, since they have the same structure, maybe I can find a way to compare them. Let me compute A and C in terms of n.Starting with A, where n = 2020:A = n/(n-1) + n/(n+1)To combine these two fractions, I can find a common denominator, which would be (n-1)(n+1) = n² - 1.So, A becomes:[n(n+1) + n(n-1)] / (n² - 1)Let me compute the numerator:n(n+1) + n(n-1) = n² + n + n² - n = 2n²So, A simplifies to:2n² / (n² - 1) = 2 + 2/(n² - 1)Wait, how did I get that? Let me check:2n² / (n² - 1) can be written as 2(n² - 1 + 1)/(n² - 1) = 2 + 2/(n² - 1). Yes, that's correct.Similarly, for C, where n = 2022:C = n/(n-1) + n/(n+1) = 2n² / (n² - 1) = 2 + 2/(n² - 1)So, both A and C can be expressed as 2 plus a fraction. The difference between them is the value of n. Since n is larger for C (2022 vs. 2020), the denominator in the fraction 2/(n² - 1) will be larger for C, making the fraction smaller. Therefore, A will have a larger value than C because the added fraction is bigger.So, A is 2 + 2/(2020² - 1) and C is 2 + 2/(2022² - 1). Since 2020² - 1 is smaller than 2022² - 1, 2/(2020² - 1) is larger than 2/(2022² - 1). Therefore, A is larger than C.And since B is exactly 2, which is less than both A and C, the largest quantity is A.Wait, let me double-check my steps to make sure I didn't make a mistake.1. For A and C, I expressed them in terms of n and found that both simplify to 2 + 2/(n² - 1). That seems correct.2. Since n is larger for C, n² - 1 is larger, making the fraction 2/(n² - 1) smaller. So, A, having a smaller n, has a larger fraction added to 2, making A larger than C. That makes sense.3. B is exactly 2, so it's the smallest among the three.Therefore, A is the largest quantity.I think that's solid. I don't see any mistakes in my reasoning.**Final Answer**boxed{A}
❓The ratio of money with Ram and Gopal is 7 : 17 and that with Gopal and Krishan is 7 : 17. If Ram has Rs. 686, how much money does Krishan have?
💡First, I need to determine how much money Gopal has based on the given ratio between Ram and Gopal.Given that Ram has Rs. 686 and the ratio of Ram's money to Gopal's money is 7:17, I can set up the equation:686 / G = 7 / 17By cross-multiplying, I find:7 * G = 686 * 17Solving for G:G = (686 * 17) / 7G = 11662 / 7G = 1666So, Gopal has Rs. 1666.Next, I need to find out how much money Krishan has using the ratio between Gopal and Krishan, which is also 7:17.Using Gopal's amount:1666 / K = 7 / 17Cross-multiplying again:7 * K = 1666 * 17Solving for K:K = (1666 * 17) / 7K = 28322 / 7K = 4046Therefore, Krishan has Rs. 4046.
❓If x#y = xy - 3x, what is the value of (8#3) - (3#8)?
💡First, I need to compute the value of (8#3) using the defined operation (x#y = xy - 3x).Calculating (8#3):[8#3 = 8 times 3 - 3 times 8 = 24 - 24 = 0]Next, I will compute the value of (3#8) using the same operation.Calculating (3#8):[3#8 = 3 times 8 - 3 times 3 = 24 - 9 = 15]Now, I need to find the difference between (8#3) and (3#8).Subtracting the two results:[(8#3) - (3#8) = 0 - 15 = -15]Therefore, the value of ((8#3) - (3#8)) is (-15).
❓An octagon ABCDEFGH has a square WXYZ inscribed in it with W on overline{BC}, X on overline{DE}, Y on overline{FG}, and Z on overline{HA}. Given AB = 50, and GH = 50(sqrt{3} - 1), determine the side-length of square WXYZ.textbf{(A)} 40sqrt{3} qquadtextbf{(B)} 50 sqrt{2} qquadtextbf{(C)} 50 qquadtextbf{(D)} 60 qquadtextbf{(E)} 70
💡Alright, so I have this problem about an octagon with a square inscribed in it. The octagon is labeled ABCDEFGH, and the square is WXYZ. The points W, X, Y, Z are on the sides BC, DE, FG, and HA respectively. They give me that AB is 50 units long, and GH is 50 times (sqrt(3) minus 1). I need to find the side length of the square WXYZ.First, I need to visualize this octagon. Since it's labeled ABCDEFGH, it's an eight-sided figure. I'm assuming it's a regular octagon, but wait, they only give me two side lengths: AB is 50, and GH is 50(sqrt(3) - 1). Hmm, so it might not be a regular octagon because the sides aren't all equal. That complicates things a bit.But the square is inscribed in the octagon, so each vertex of the square lies on a different side of the octagon. That means W is on BC, X is on DE, Y is on FG, and Z is on HA. Since it's a square, all its sides are equal, and all its angles are 90 degrees.I think I need to use some properties of octagons and squares to relate the given side lengths to the side length of the square. Maybe coordinate geometry could help here. If I can assign coordinates to the vertices of the octagon, I might be able to find the coordinates of W, X, Y, Z and then compute the distances to find the side length of the square.But before jumping into coordinates, let me think if there's a simpler way. Maybe using similar triangles or some trigonometric relationships. Since it's an octagon, the internal angles are known. In a regular octagon, each internal angle is 135 degrees, but since this isn't regular, maybe the angles are different. Hmm, but without knowing more side lengths, it's hard to say.Wait, maybe the octagon is symmetric in some way. If AB is 50 and GH is 50(sqrt(3) - 1), perhaps the octagon has some reflection symmetry or rotational symmetry. If I can figure out the positions of the square's vertices relative to the octagon's sides, I might be able to set up some equations.Let me try to sketch the octagon. Let's say it's convex, which is typical. Starting from A, going to B, then C, D, E, F, G, H, and back to A. The square is inside, with W on BC, X on DE, Y on FG, Z on HA. So, the square is kind of rotated inside the octagon.Since the square has right angles, the sides of the square will intersect the sides of the octagon at certain points. Maybe I can use the slopes of the sides of the octagon and the square to find where they intersect.Alternatively, maybe I can use vectors or coordinate geometry. Let me try setting up a coordinate system. Let's place point A at the origin (0,0). Then, since AB is 50, and assuming AB is along the x-axis, point B would be at (50,0). Now, I need to figure out the coordinates of the other points.But wait, without knowing the angles or the other sides, it's tricky. Maybe I can assume some symmetry. If the octagon is symmetric with respect to the x-axis, then point H would be somewhere on the y-axis, but I'm not sure.Alternatively, maybe the octagon is such that sides AB and GH are parallel. If AB is 50 and GH is 50(sqrt(3) - 1), perhaps they are on opposite sides of the octagon. Then, the square is inscribed such that its sides are at 45 degrees to the sides of the octagon.Wait, maybe I can consider the distances from the center of the octagon to the sides. If the square is inscribed, its center might coincide with the center of the octagon. But I don't know the coordinates of the center.Hmm, this is getting complicated. Maybe I should look for similar triangles or use the Law of Sines or Cosines somewhere.Let me think about triangle ABW. Since W is on BC, and the square has side length x, maybe BW is equal to x? Or is it something else? Wait, no, because W is on BC, which is a side of the octagon. So, BW would be a segment on BC, but BC isn't necessarily equal to AB.Wait, in a regular octagon, all sides are equal, but here they aren't. So, BC could be a different length. Hmm, but I don't know BC's length. Maybe I can express BC in terms of AB and GH?Alternatively, maybe I can use the fact that the square is inscribed, so the sides of the square are at 45 degrees to the sides of the octagon. That might create some right triangles or something.Wait, another approach: Since the square is inscribed, the lines from the center of the octagon to the vertices of the square might form some angles. If I can find those angles, I can relate them to the side lengths.But without knowing the exact shape of the octagon, it's hard to proceed. Maybe I need to make some assumptions. Let's assume that the octagon is such that sides AB and GH are parallel, and the square is inscribed symmetrically with respect to these sides.If AB is 50 and GH is 50(sqrt(3) - 1), maybe the distance between these two sides is related to the side length of the square. If I can find the distance between AB and GH, then perhaps I can relate it to the square's side.Wait, the distance between two parallel sides in a regular octagon can be calculated, but since this isn't regular, I'm not sure. Maybe I can use the given side lengths to find the distance.Alternatively, maybe the side length of the square can be found by considering the ratio of AB to GH. Since AB is 50 and GH is 50(sqrt(3) - 1), the ratio is 1 to (sqrt(3) - 1). Maybe this ratio is related to the square's side.Wait, sqrt(3) - 1 is approximately 0.732, so the ratio is about 1.366. Maybe the side length of the square is 50 divided by something.Alternatively, maybe I can use similar triangles. If I consider the triangles formed by the sides of the octagon and the square, maybe they are similar, and I can set up a proportion.Wait, let me try to think step by step.1. Let the side length of the square be x.2. Since W is on BC, X is on DE, Y is on FG, and Z is on HA, the square is kind of "tilted" inside the octagon.3. The sides of the square will intersect the sides of the octagon at certain points, creating triangles outside the square but inside the octagon.4. Maybe these triangles are similar, so I can set up proportions.5. For example, triangle ABW and triangle HGZ might be similar because of the symmetry.6. If AB is 50 and GH is 50(sqrt(3) - 1), then the ratio of similarity is 50 / [50(sqrt(3) - 1)] = 1 / (sqrt(3) - 1).7. Rationalizing the denominator, that's (sqrt(3) + 1)/2.8. So, if triangle ABW is similar to triangle HGZ with ratio (sqrt(3) + 1)/2, then the sides of these triangles are in that ratio.9. If BW is a side of triangle ABW, and GZ is a side of triangle HGZ, then BW / GZ = (sqrt(3) + 1)/2.10. But since WXYZ is a square, BW and GZ might be related to the side length x.Wait, I'm getting confused. Maybe I need to draw a diagram.But since I can't draw, I'll try to imagine it.Let me consider the side AB = 50. Point W is on BC. So, BW is a segment on BC. Similarly, Z is on HA, so HZ is a segment on HA.If I can find the lengths BW and HZ in terms of x, maybe I can relate them.Wait, in a regular octagon, the distance from a vertex to the point where the square touches the side can be related to the side length of the square. But since this isn't regular, I need another approach.Wait, maybe using coordinates is the way to go. Let's try that.Let me place point A at (0,0). Then, since AB is 50, point B is at (50,0). Now, I need to figure out the coordinates of the other points.But without knowing the angles or the lengths of the other sides, it's difficult. Maybe I can assume that the octagon is symmetric with respect to the x-axis. So, point H would be somewhere on the y-axis, but I'm not sure.Wait, maybe the octagon is such that sides AB and GH are horizontal, with AB at the bottom and GH at the top. Then, the square is inscribed vertically.If that's the case, the vertical distance between AB and GH would be related to the side length of the square.But I don't know the vertical distance. Hmm.Wait, maybe I can use the fact that in a regular octagon, the distance between two parallel sides is related to the side length. But since this isn't regular, I need to adjust.Alternatively, maybe I can use the given side lengths AB and GH to find the distance between them.Wait, if AB is 50 and GH is 50(sqrt(3) - 1), maybe the distance between AB and GH is proportional to the side length of the square.Wait, I'm not making progress. Maybe I need to think differently.Let me consider the triangles formed by the square and the octagon.Since W is on BC, X is on DE, Y is on FG, and Z is on HA, the square creates four triangles outside of it within the octagon.If I can find the areas of these triangles or relate their sides, maybe I can find x.Wait, another idea: Since the square is inscribed, the lines from the center of the octagon to the vertices of the square might bisect the angles of the octagon.But without knowing the center or the angles, it's hard.Wait, maybe I can use the fact that the sides of the square are equal and at right angles, so the slopes of the sides of the square can be used to find the coordinates.Wait, let me try to assign coordinates step by step.Let me place point A at (0,0). Then, AB is along the x-axis to (50,0). Now, I need to figure out where point B is connected to point C.But without knowing the angle at B, I can't determine the coordinates of C. Hmm.Wait, maybe I can assume that the octagon is such that each side makes a 45-degree angle with the previous one. But that's for a regular octagon. Since this isn't regular, I can't assume that.Wait, maybe I can use vectors. If I can express the sides as vectors, I can find the coordinates.But I don't have enough information about the other sides. Only AB and GH are given.Wait, maybe I can consider the octagon as a combination of rectangles and triangles. But I'm not sure.Wait, another approach: Since the square is inscribed, the sides of the square must intersect the sides of the octagon at specific points. Maybe I can set up equations for the lines of the octagon and the square and solve for the intersection points.But without knowing the equations of the octagon's sides, it's difficult.Wait, maybe I can use the fact that the side length of the square relates to the difference between AB and GH.Given AB = 50 and GH = 50(sqrt(3) - 1), the difference is 50 - 50(sqrt(3) - 1) = 50(2 - sqrt(3)).Hmm, 2 - sqrt(3) is approximately 0.2679, so 50 times that is about 13.4.But I don't see how that relates to the square's side length.Wait, maybe the side length of the square is 50 divided by something.Wait, let me think about similar problems. In a regular octagon, the side length of an inscribed square can be found using trigonometric relationships.In a regular octagon with side length s, the distance from the center to a side is (s/2)(1 + sqrt(2)). But since this isn't regular, I can't use that.Wait, maybe I can use the Law of Sines or Cosines in some triangles.Let me consider triangle ABW. If I can find the angles, I can relate the sides.But I don't know the angles. Hmm.Wait, maybe the angle at B is 135 degrees, as in a regular octagon. But since this isn't regular, I can't assume that.Wait, but maybe the angle is still 135 degrees because the octagon is symmetric. If AB and BC are sides meeting at B, and the octagon is convex, the internal angle at B is likely 135 degrees.Wait, in a regular octagon, each internal angle is 135 degrees. So, maybe even though the sides aren't equal, the internal angles are still 135 degrees.If that's the case, then I can use that information.So, at point B, the internal angle is 135 degrees. So, the angle between AB and BC is 135 degrees.Similarly, at point H, the internal angle is 135 degrees.So, if I can model the octagon with internal angles of 135 degrees, even if the sides aren't equal, I can use that.So, let's proceed with that assumption.So, at point B, angle ABC is 135 degrees.Similarly, at point H, angle GHA is 135 degrees.Now, since W is on BC, and Z is on HA, and WXYZ is a square, the lines BW and HZ are sides of the triangles ABW and HGZ.Wait, maybe triangles ABW and HGZ are similar because they both have a 135-degree angle.If that's the case, then the ratio of their sides is equal.Given AB = 50 and GH = 50(sqrt(3) - 1), the ratio of AB to GH is 1 to (sqrt(3) - 1).So, if triangles ABW and HGZ are similar, then the ratio of BW to GZ is the same as AB to GH, which is 1 to (sqrt(3) - 1).So, BW / GZ = 1 / (sqrt(3) - 1).But since WXYZ is a square, the segments BW and GZ might be related to the side length x.Wait, maybe BW and GZ are equal to x?Wait, no, because W is on BC and Z is on HA, which are different sides.Wait, maybe BW and GZ are the projections of the square's sides onto the sides of the octagon.Wait, this is getting confusing. Maybe I need to use the Law of Sines in triangles ABW and HGZ.In triangle ABW, angle at B is 135 degrees, side AB is 50, and side BW is opposite to angle at W.Similarly, in triangle HGZ, angle at H is 135 degrees, side GH is 50(sqrt(3) - 1), and side GZ is opposite to angle at Z.If the triangles are similar, then the ratio of sides is equal.So, AB / GH = BW / GZ = AW / HZ.Given AB = 50, GH = 50(sqrt(3) - 1), so AB / GH = 1 / (sqrt(3) - 1).So, BW / GZ = 1 / (sqrt(3) - 1).Let me rationalize that: 1 / (sqrt(3) - 1) = (sqrt(3) + 1)/2.So, BW / GZ = (sqrt(3) + 1)/2.But I don't know BW or GZ yet.Wait, but since WXYZ is a square, the length from W to X is x, and the same for X to Y, Y to Z, Z to W.Also, the angles at W, X, Y, Z are 90 degrees.Wait, maybe I can relate BW and GZ to x using the Law of Sines.In triangle ABW, angle at B is 135 degrees, angle at W is something, and angle at A is something.Wait, but I don't know the other angles.Wait, maybe I can consider that the line from W to X is perpendicular to the line from X to Y, and so on.Wait, this is getting too vague. Maybe I need to set up coordinates.Let me try again with coordinates.Let me place point A at (0,0). Then, AB is along the x-axis to (50,0). Now, I need to figure out the coordinates of point B, which is (50,0).Now, the internal angle at B is 135 degrees, so the side BC makes a 135-degree angle with AB.Since AB is along the x-axis, the direction from B to C is 135 degrees from AB.So, the slope of BC is tan(135 degrees) = tan(180 - 45) = -1.So, the line BC has a slope of -1.Similarly, the internal angle at H is 135 degrees, so the side HA makes a 135-degree angle with GH.But I don't know where point H is yet.Wait, maybe I can find the coordinates of point C.Since BC has a slope of -1, and point B is at (50,0), the line BC is y = -1(x - 50) = -x + 50.Now, I need to find the length of BC. But I don't know it. Hmm.Wait, but maybe I can express the coordinates of point C as (50 - t, t), where t is the length along the x-axis from B to C.Wait, no, because the slope is -1, so for every unit you move left, you move up 1 unit.So, if I move t units left from B, I move t units up, so point C is at (50 - t, t).Similarly, the length BC is t*sqrt(2), because it's a 45-45-90 triangle.But I don't know t yet.Wait, but maybe I can relate t to the side length of the square.Since W is on BC, and WXYZ is a square, the coordinates of W can be expressed in terms of t and x.Wait, this is getting complicated, but let's proceed.Let me denote the side length of the square as x.Since W is on BC, which goes from (50,0) to (50 - t, t), the coordinates of W can be parameterized.Let me say that W divides BC in the ratio k:1, so the coordinates of W are:W_x = (50*1 + (50 - t)*k)/(k + 1)W_y = (0*1 + t*k)/(k + 1)But I don't know k yet.Alternatively, since W is a vertex of the square, the line from W to X is perpendicular to the line from X to Y, and so on.Wait, maybe I can use vectors.Let me denote the vector from W to X as (a,b), then the vector from X to Y would be (-b,a) because it's a 90-degree rotation.But since WXYZ is a square, all sides are equal, so sqrt(a^2 + b^2) = x.But I don't know a and b.Wait, maybe I can express the coordinates of X, Y, Z in terms of W and the vectors.But without knowing where W is, it's difficult.Wait, maybe I can use the fact that the square is inscribed, so the lines from W, X, Y, Z are all at 45 degrees to the sides of the octagon.Wait, I'm not making progress. Maybe I need to look for a different approach.Wait, another idea: Since the square is inscribed, the distance from the center of the octagon to each side is equal to half the diagonal of the square.But I don't know the center or the distances.Wait, maybe I can use the fact that the side length of the square relates to the difference in lengths of AB and GH.Given AB = 50 and GH = 50(sqrt(3) - 1), the difference is 50 - 50(sqrt(3) - 1) = 50(2 - sqrt(3)).Hmm, 2 - sqrt(3) is approximately 0.2679, so 50 times that is about 13.4.But I don't see how that relates to the square's side length.Wait, maybe the side length of the square is 50 divided by something.Wait, another approach: Let's consider the octagon as a combination of a rectangle and two isosceles right triangles on the top and bottom.But I don't know if that's the case.Wait, maybe I can think of the octagon as a square with its corners cut off, but since it's not regular, the cuts might not be equal.Wait, but if I can model it that way, the side length of the square could be related to the original square and the cuts.But without knowing the cuts, it's hard.Wait, maybe I can use the fact that the side length of the square is the geometric mean of AB and GH.So, x = sqrt(AB * GH) = sqrt(50 * 50(sqrt(3) - 1)) = 50 sqrt(sqrt(3) - 1).But sqrt(sqrt(3) - 1) is approximately sqrt(0.732) ≈ 0.855, so x ≈ 50 * 0.855 ≈ 42.75, which isn't one of the options. So, that can't be right.Wait, another idea: Maybe the side length of the square is the harmonic mean of AB and GH.So, x = 2/(1/AB + 1/GH) = 2/(1/50 + 1/[50(sqrt(3)-1)]) = 2/( (sqrt(3)-1 + 1)/[50(sqrt(3)-1)] ) = 2/( sqrt(3)/[50(sqrt(3)-1)] ) = 2 * [50(sqrt(3)-1)] / sqrt(3) = 100(sqrt(3)-1)/sqrt(3).Simplify: 100(sqrt(3)-1)/sqrt(3) = 100(1 - 1/sqrt(3)) ≈ 100(1 - 0.577) ≈ 100(0.423) ≈ 42.3, which is still not an option.Hmm, maybe I'm overcomplicating it.Wait, let's think about the triangles formed by the square and the octagon.If I consider triangle ABW, it's a triangle with side AB = 50, angle at B = 135 degrees, and side BW = x (assuming BW is equal to the square's side). Wait, is BW equal to x?Wait, no, because W is on BC, and BW is a segment on BC, not necessarily equal to x.Wait, but if WXYZ is a square, then the distance from W to X is x, and the angle at W is 90 degrees.Wait, maybe I can use the Law of Sines in triangle ABW.In triangle ABW, angle at B is 135 degrees, side AB = 50, and side BW = let's say y.Then, by the Law of Sines:AB / sin(angle at W) = BW / sin(angle at A)But I don't know the angles at W and A.Wait, but maybe angle at A is 45 degrees because the square creates a 45-degree angle.Wait, no, because the square is inscribed, the angle at A is still part of the octagon.Wait, I'm stuck.Wait, maybe I can consider that the side length of the square is 50, which is one of the options. Let me check if that makes sense.If x = 50, then the square has sides of 50. Given that AB is 50, that would mean that BW is 50, but BC might be longer than 50, which is possible.But I need to verify.Wait, if x = 50, then the side length of the square is 50, which is option C. Maybe that's the answer.But I need to be sure.Wait, another approach: Since the octagon has sides AB = 50 and GH = 50(sqrt(3) - 1), and the square is inscribed, the side length of the square is likely 50, as it's a common answer and fits the given options.So, I think the answer is 50, which is option C.
❓Ancient Hindu mathematicians used the following rational approximation for the number sqrt{2}:t=1+frac{1}{3}+frac{1}{3 cdot 4}-frac{1}{3 cdot 4 cdot 34}What is the maximum percentage error of this approximation? How many leading digits do t and the decimal approximation of sqrt{2} have in common?
💡Okay, so I have this problem about an ancient Hindu approximation for the square root of 2. The approximation is given as:t = 1 + frac{1}{3} + frac{1}{3 cdot 4} - frac{1}{3 cdot 4 cdot 34}And I need to find two things: the maximum percentage error of this approximation and how many leading digits t and the decimal approximation of √2 have in common.First, I need to understand what this approximation is. It looks like a series of fractions added and subtracted. So, maybe I should compute the value of t step by step.Let me start by calculating each term separately:1. The first term is 1, which is straightforward.2. The second term is 1/3. I know that 1/3 is approximately 0.333333...3. The third term is 1/(3*4). Let me compute that: 3*4 is 12, so 1/12 is approximately 0.083333...4. The fourth term is -1/(3*4*34). Let's compute the denominator first: 3*4 is 12, and 12*34 is 408. So, 1/408 is approximately 0.00245098... and since it's subtracted, it's -0.00245098...Now, adding all these up:t = 1 + 0.333333... + 0.083333... - 0.00245098...Let me add them step by step:1 + 0.333333 = 1.333333...1.333333 + 0.083333 = 1.416666...1.416666 - 0.00245098 ≈ 1.414215...So, t is approximately 1.414215.Now, I know that √2 is approximately 1.41421356... So, t is about 1.414215, which is very close to √2.First, let's compute the maximum percentage error. To find the percentage error, I need to compare the approximation t to the actual value √2.The formula for percentage error is:text{Percentage Error} = left| frac{text{Approximation} - text{Actual Value}}{text{Actual Value}} right| times 100%So, plugging in the values:Approximation (t) ≈ 1.414215Actual Value (√2) ≈ 1.41421356Difference: 1.414215 - 1.41421356 ≈ 0.00000144Now, compute the percentage error:left| frac{0.00000144}{1.41421356} right| times 100% ≈ left( 0.00000102 right) times 100% ≈ 0.000102%So, the maximum percentage error is approximately 0.000102%.Now, the second part: how many leading digits do t and √2 have in common?Let's write out both numbers to more decimal places to compare:t ≈ 1.414215...√2 ≈ 1.41421356...Let's compare digit by digit:1.41421356...1.414215...Comparing each digit after the decimal:1.41421356...1.414215...So, the first digit after the decimal is 4 in both.Second digit: 1 in both.Third digit: 4 in both.Fourth digit: 2 in both.Fifth digit: 1 in both.Sixth digit: 3 vs. 5. Here they differ.So, up to the fifth decimal place, they are the same. Therefore, they have 6 leading digits in common (including the 1 before the decimal).Wait, let me count again:1.41421356...1.414215...So, the integer part is 1, same.First decimal: 4, same.Second: 1, same.Third: 4, same.Fourth: 2, same.Fifth: 1, same.Sixth: 3 vs. 5, different.So, up to the fifth decimal place, they are the same. That means 6 digits in total (including the 1 before the decimal point). So, 6 leading digits are the same.Wait, but sometimes people count leading digits without the decimal point. Let me check:t ≈ 1.414215√2 ≈ 1.41421356So, writing them aligned:1.4142151.41421356Comparing each digit:1 vs 1: same. vs .: same4 vs 4: same1 vs 1: same4 vs 4: same2 vs 2: same1 vs 1: same5 vs 3: differentSo, up to the seventh digit after the decimal, they start to differ. Wait, but in t, after 1.414215, the next digit is not given, but in √2, it's 1.41421356...Wait, maybe I confused the decimal places.Wait, t is 1.414215...√2 is 1.41421356...So, t is 1.414215...√2 is 1.41421356...So, let's write them aligned:1.414215...1.41421356...So, the first six digits after the decimal in t are 414215In √2, the first six digits after the decimal are 414213So, comparing:4 vs 4: same1 vs 1: same4 vs 4: same2 vs 2: same1 vs 1: same5 vs 3: differentSo, up to the fifth decimal place, they are the same. Therefore, the first five decimal places are the same, making the total number of leading digits in common as 6 (including the 1 before the decimal).Wait, but sometimes leading digits are counted from the first non-zero digit, which is 1 here. So, 1 is the first leading digit, then 4, 1, 4, 2, 1, and then they differ at the sixth decimal place.So, the number of leading digits in common is 6.Wait, but let me check the exact decimal expansions:t = 1.414215...√2 ≈ 1.41421356...So, t is 1.414215...√2 is 1.41421356...So, the first five digits after the decimal are 41421 in both, and then t has 5 while √2 has 3. So, up to the fifth decimal place, they are the same. Therefore, the number of leading digits in common is 6 (including the 1 before the decimal).Alternatively, if we count the digits without considering the decimal point, it's 1.414213... and 1.414215..., so the first six digits are 1,4,1,4,2,1, and then they differ at the seventh digit.Wait, but in t, it's 1.414215..., so the seventh digit is 5, while in √2, it's 1.41421356..., so the seventh digit is 3. So, up to the sixth digit after the decimal, they are the same? Wait, no.Wait, let me write them out:t: 1.414215...√2: 1.41421356...So, t is 1.414215...√2 is 1.41421356...So, the first six digits after the decimal in t are 414215In √2, the first six digits after the decimal are 414213So, comparing:1st: 4 vs 4: same2nd: 1 vs 1: same3rd: 4 vs 4: same4th: 2 vs 2: same5th: 1 vs 1: same6th: 5 vs 3: differentSo, up to the fifth decimal place, they are the same. Therefore, the number of leading digits in common is 6 (including the 1 before the decimal).Wait, but sometimes people count leading digits as the number of digits from the left that are the same before the first difference. So, in this case, 1.414213 vs 1.414215, the first six digits are 1,4,1,4,2,1, and then they differ at the seventh digit (3 vs 5). So, the number of leading digits in common is 6.Alternatively, if we consider the decimal places, up to the fifth decimal place, they are the same, making the total number of leading digits (including the integer part) as 6.I think that's the correct way to count it. So, the answer is 6 leading digits in common.So, to summarize:- Maximum percentage error is approximately 0.000102%- Number of leading digits in common is 6.But let me double-check the percentage error calculation.We have t ≈ 1.414215√2 ≈ 1.41421356Difference: t - √2 ≈ 1.414215 - 1.41421356 ≈ 0.00000144Percentage error: (0.00000144 / 1.41421356) * 100 ≈ (0.00000102) * 100 ≈ 0.000102%Yes, that seems correct.Alternatively, sometimes percentage error is calculated as (|t - √2| / √2) * 100, which is what I did.So, the maximum percentage error is approximately 0.000102%, and the number of leading digits in common is 6.I think that's it.