Q64 / 160 · AP EAMCET 2024 (18 May Shift 1) · Mathematics
$\tan ^{-1} 2+\tan ^{-1} 3=$
- A$-\frac{\pi}{4}$
- B$\frac{\pi}{4}$
- Correct answerC$\frac{3 \pi}{4}$
- D$\frac{5 \pi}{4}$
Solution
$\begin{aligned} & \text { Since, } \tan ^{-1} 2+\tan ^{-1}(3) \\ = & \pi+\tan ^{-1}\left(\frac{2+3}{1-2 \times 3}\right)=\pi+\tan ^{-1}\left(\frac{5}{-5}\right)\end{aligned}$
$=\pi+\tan ^{-1}(-1)=\pi-\frac{\pi}{4}=\frac{3 \pi}{4}$
Hence, the correct answer is option: 'C'.