If alpha=cos^-1(3/5) , beta=tan^-1(1/3), where 0<alpha,beta<π/4 , then alpha-beta is equal to

Question

If α=cos^{​​​​-1}(3/5) , β=tan^{​​​​-1}(1/3), where 0<α,β<π/4 , then α-β is equal to 

A) \(\sin^{-1} {9\over5\sqrt{10}}\) 

B)\(\tan^{-1} ({9\over14})\) 

C)\(\cos^{-1} {9\over5\sqrt{10}}\) 

D)\(\tan^{-1} ({9\over5\sqrt{10}})\)

Answer 1

Correct answer is A) \(\sin^{-1} {9\over5\sqrt{10}}\) 

Detailed answer