Derivative of cot-1[1+sinx+1-sinx1+sinx-1-sinx], 0<x<π2 is:
(1)
Ans. 12
Explanation:
Let y=cot-1(1+sinx+1-sinx1+sinx-1-sinx)
y=cot-1[(cosx2+sinx2)+(cosx2-sinx2)(cosx2+sinx2)-(cosx2-sinx2)]
⇒ y=cot-1(2cosx22sinx2)=cot-1(cotx2)=x2
∴ dydx=12