Question:
Mark $(\sqrt{)}$ against the correct answer in each of the following:
$\int \cos x \sqrt{9-\sin ^{2} x} d x=?$
A. $\frac{1}{2} \sin x \sqrt{9-\sin ^{2} x}+\frac{9}{2} \sin ^{-1}\left(\frac{\sin x}{3}\right)+C$
B. $\frac{\sin x}{2} \sqrt{9-\sin ^{2} x}+\frac{9}{2} \sin ^{-1}\left(\frac{\sin x}{3}\right)+C$
C. $\frac{1}{2} \cos x \sqrt{9-\sin ^{2} x}+\frac{9}{2} \sin ^{-1}\left(\frac{\sin x}{3}\right)+C$
D. none of these
Solution:
