Question

Prove that : `tan1/2{sin^(-1)(2x)/(1+x^2)+cos^(-1)(1-y^2)/(1+y^2)}=(x+y)/(1-x y)` , if `|x|<1,` `y >0` and `x y<1` .<br>A. `(x-y)/(1+xy)`
B. `(y-x)/(1+xy)`
C. `(x+y)/(1-xy)`
D. `(x+y)/(xy-1)`

Answer 1

Correct Answer - C