jee-advanced 2001 Q34

jee-advanced · India · screening Stationary points and optimisation Inverse trigonometric equation
34. $\sin - 1 ( x - x 2 / 2 + x 3 / 4 - \ldots ) + \cos - 1 ( x 2 - x 4 / 2 + x 6 / 4 - \ldots ) = n / 2$ for $0 < | x | < \sqrt { } ( 2$, ) then $x$ equals :
(A) $\frac { 1 } { 2 }$
(B) 1
(C) $- 1 / 2$
(D) - 1
34. $\sin - 1 ( x - x 2 / 2 + x 3 / 4 - \ldots ) + \cos - 1 ( x 2 - x 4 / 2 + x 6 / 4 - \ldots ) = n / 2$ for $0 < | x | < \sqrt { } ( 2$, ) then $x$ equals :\\
(A) $\frac { 1 } { 2 }$\\
(B) 1\\
(C) $- 1 / 2$\\
(D) - 1\\