Question

The number of real solutions of

tan^–1 $\sqrt { x ( x + 1 ) }$ + sin^–1 $\sqrt { x ^ { 2 } + x + 1 }$ = $\frac { \pi } { 2 }$ is

• A. Zero
• B. One
• C. Two
• D. Infinite

Answer 1

Answer: (C)

Two

Answer 2

tan^–1$\frac { \pi } { 2 }$

cos^–1$\frac { \pi } { 2 }$

=

\x(x + 1) = 0 Ž x = 0, x = –1