$\int \frac{d x}{\sqrt{9-x^{2}}}$ সমান-

$\sin ^{-1}\left(\frac{x}{3}\right)+c$

$\cos ^{-1}\left(\frac{x}{3}\right)+c$

$\sin ^{-1}\left(\frac{3}{x}\right)+c$

$\cos ^{-1}\left(\frac{3}{x}\right)+c$