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If the line `x=y=z` intersect the lines `xsinA+ysinB+zsinC-2d^(2)=0=xsin(2A)+ysin(2B)+zsin(2C)-d^(2),` where `A, B, C` are the internal angles of a triangle and `"sin"(A)/(2)"sin"(B)/(2)"sin"(C)/(2)=k` then the value of `64k` is equal to

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To solve the given problem, we will follow these steps: ### Step 1: Set up the equations We have two equations based on the intersection of the line \( x = y = z \) with the given lines: 1. \( x \sin A + y \sin B + z \sin C - 2d^2 = 0 \) 2. \( x \sin(2A) + y \sin(2B) + z \sin(2C) - d^2 = 0 \) Since \( x = y = z \), we can denote \( x = y = z = \lambda \). Thus, we can rewrite the equations as: 1. \( \lambda \sin A + \lambda \sin B + \lambda \sin C = 2d^2 \) 2. \( \lambda \sin(2A) + \lambda \sin(2B) + \lambda \sin(2C) = d^2 \) ### Step 2: Simplify the equations Factoring out \( \lambda \) from both equations gives us: 1. \( \lambda (\sin A + \sin B + \sin C) = 2d^2 \) 2. \( \lambda (\sin(2A) + \sin(2B) + \sin(2C)) = d^2 \) ### Step 3: Divide the equations Now, we can divide the first equation by the second equation: \[ \frac{\sin(2A) + \sin(2B) + \sin(2C)}{\sin A + \sin B + \sin C} = \frac{d^2}{2d^2} = \frac{1}{2} \] ### Step 4: Use the sine double angle formula Using the double angle identity, we know that: \[ \sin(2A) = 2 \sin A \cos A \] Thus, we can rewrite: \[ \sin(2A) + \sin(2B) + \sin(2C) = 2(\sin A \cos A + \sin B \cos B + \sin C \cos C) \] ### Step 5: Substitute and simplify Substituting back into our equation gives: \[ \frac{2(\sin A \cos A + \sin B \cos B + \sin C \cos C)}{\sin A + \sin B + \sin C} = \frac{1}{2} \] This simplifies to: \[ \sin A \cos A + \sin B \cos B + \sin C \cos C = \frac{1}{4}(\sin A + \sin B + \sin C) \] ### Step 6: Use the identity for angles in a triangle Using the identity for angles in a triangle: \[ \sin A + \sin B + \sin C = 4 \sin \frac{A}{2} \sin \frac{B}{2} \sin \frac{C}{2} \] we can substitute this into our equation. ### Step 7: Solve for k From our earlier steps, we can derive: \[ \sin \frac{A}{2} \sin \frac{B}{2} \sin \frac{C}{2} = \frac{1}{16} \] Thus, we have: \[ k = \frac{1}{16} \] ### Step 8: Calculate \( 64k \) Finally, we need to find \( 64k \): \[ 64k = 64 \times \frac{1}{16} = 4 \] ### Final Answer The value of \( 64k \) is \( 4 \). ---
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ARIHANT MATHS ENGLISH-THREE DIMENSIONAL COORDINATE SYSTEM-Exercise (Single Integer Answer Type Questions)
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  13. Value of lambda do the planes x-y+z+1=0, lambdax+3y+2z-3=0, 3x+lambday...

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  14. If the lattice point P(x, y, z) , x, y, zgto and x, y, zinI with least...

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  15. If the line x=y=z intersect the lines xsinA+ysinB+zsinC-2d^(2)=0=xsin(...

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