Q. $cos (2 tan^{- 1} (\frac{1}{5})) =$

1991 232 Inverse Trigonometric Functions Report Error

A

$\frac{12}{13}$

60%

B

$\frac{24}{25}$

24%

C

$\frac{26}{25}$

8%

D

$\frac{13}{12}$

8%

Solution:

$2 tan^{- 1} x = cos^{- 1} (\frac{1 - x ^{2}}{1 + x ^{2}})$