Practicing Success

Target Exam

CUET

Subject

-- Mathematics - Section B1

Chapter

Inverse Trigonometric Functions

Question:

Value of $tan^{-1}2+tan^{-1}3+tan^{-1}4$ is equal to :

Options:

$\pi +tan^{-1}\frac{3}{5}$

$\pi - tan^{-1}\frac{3}{5}$

$\pi - tan^{-1}\frac{5}{3}$

$\pi + tan^{-1}\frac{5}{3}$

Correct Answer:

$\pi +tan^{-1}\frac{3}{5}$

Explanation:

$\tan^{-1}2+\tan^{-1}3+\tan^{-1}4$

$=π+\tan^{-1}\left(\frac{2+3}{1-2×3}\right)+\tan^{-1}4$ (π add as 1-2.3<0)

so $π-\tan^{-1}1+\tan^{-1}4$

$=π+\tan^{-1}\left(\frac{4-1}{1+4.1}\right)$

$=π+\tan^{-1}\left(\frac{3}{5}\right)$