Question

If the inverse trigonometric functions take principal values, then ${\cos }^{-1}\left(\frac{3}{10}\cos \left({\tan }^{-1}\left(\frac{4}{3}\right)\right)+\frac{2}{5}\sin \left({\tan }^{-1}\left(\frac{4}{3}\right)\right)\right)$ equal to

• A. 0
• B. $\frac{\pi }{4}$
• C. $\frac{\pi }{3}$
• D. $\frac{\pi }{6}$

Answer 1

Answer: (B)

Correct answer is (b) $\frac{\pi }{4}$