Inverse Trigonometric Functions Question 143
Question: $ \cos ( {{\sin }^{-1}}\frac{5}{13} )= $
Options:
A) $ \frac{12}{13} $
B) $ -\frac{12}{13} $
C) $ \frac{5}{12} $
D) None of these
Show Answer
Answer:
Correct Answer: A
Solution:
Let $ {{\sin }^{-1}}\frac{5}{13}=x\Rightarrow \sin x=\frac{5}{13} $
$ \Rightarrow \cos x=\sqrt{1-\frac{25}{169}}=\frac{12}{13} $
$ \Rightarrow \cos ( {{\sin }^{-1}}\frac{5}{13} )=\cos ( {{\cos }^{-1}}\frac{12}{13} )=\frac{12}{13} $ .
BETA
