∫ cos(2cot^{-1} √1-x/1+x) dx; x ∈ [1/4, 3/4] =

Question

\(\int \limits_{\frac14}^\frac34 \cos\left(2 \cot^{-1} \sqrt{\frac {1-x}{1+x}}\right)dx =\)

(A) \(\frac{-1}4\)

(B) \(\frac 32\)

(C) \(\frac 1{16}\)

(D) \(\frac{-4}3\)

Answer 1

Correct option is (1) \(\frac{-1}4\)