Question

#Math Minoan

Solve it!!!!

Answer 1

option d is correct tan-1(a/b) is nothing but right most angle...

Answer 2

Hey there!

KINDLY SEE THE ATTACHMENT ALSO.

$tan^{-1} (\frac{a}{b} )$

tan∅ = a/b -----(1)

∴  $cos[ tan^{-1} ( \frac{a}{b})]$

   = cos∅ [From Eqn. 1]

⇒ $\frac{b}{ \sqrt{ a^{2} + b^{2} } }$

Hence, 
Option. [D] is correct.

HOPE IT HELPED ^_^