Q56 / 160 · WBJEE 2011 · Mathematics
If \(\theta+\phi=\frac{\pi}{4}\), then \((1+\tan \theta)(1+\tan \phi)\) is equal to
- A1
- Correct answerB2
- C\(5 / 2\)
- D\(1 / 3\)
Solution
\(\begin{aligned}
& \text { Hints: }(1+\tan \theta)\left(1+\frac{(1-\tan \theta)}{1+\tan \theta}\right) \\
& =(1+\tan \theta) \frac{2}{1+\tan \theta}=2
\end{aligned}\)
Hence, the correct answer is option: 'B'.