Question

if cot theta =7/8:
1.(1+sintheta)(1-sintheta)
/(1+costheta)(1-costheta)

2.cot2theta

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Answer 1

$answer$

Hi friend,

given is cotθ=7/8 ⇒ opposite side = 8 and adjacent side=7 so, hypotenuse will be squareroot of sum of sqaures of 7 and 8 i.e sqrt7^2+8^2=√113 so now sinθ=8/√113 and cosθ=7/√113

(1+sinθ)(1-sinθ)/(1+cotθ)(1-cosθ)=1-sin^2θ/1+cotθ(1-cosθ)

                                                       = 1-64/113/1+7/8(1-7/√113)

on solving we get                         49/(√113-7)√113