If

Question:

If $\frac{\pi}{2}

Solution:

$\because \frac{\pi}{2}

$\therefore \sqrt{\frac{1+\cos 2 x}{2}}=\sqrt{\frac{2 \cos ^{2} x}{2}}=|\cos x|$

In second quadrant $\cos x$ is negative.

$\therefore \sqrt{\frac{1+\cos 2 x}{2}}=-\cos x$

Leave a comment

Close

Click here to get exam-ready with eSaral

For making your preparation journey smoother of JEE, NEET and Class 8 to 10, grab our app now.

Download Now