Question

Find the value of x which satisfy equation ${\cot }^{-1}x+{\tan }^{-1}3=\frac{\pi }{2}$

• A. -3
• B. -1/3
• C. 1/3
• D. 3

Answer 1

Answer: (D)

3

Given, ${\cot }^{-1}x+{\tan }^{-1}3=\frac{\pi }{2}$

$\because {\tan }^{-1}\theta +{\cot }^{-1}\theta =\frac{\pi }{2}$
$\therefore {\cot }^{-1}x+{\tan }^{-1}3=\frac{\pi }{2}\Rightarrow x=3$