## Calculus 10th Edition

$\int \frac{du}{\sqrt {a^{2}-u^{2}}}$ $u=t$ $a=1$
Try it: $u=t$ $du=dt$ $\int \frac{du}{\sqrt {a^{2}-u^{2}}}=arcsin\frac{u}{a}+C$ $3arcsint+C$ $\int \frac{du}{\sqrt {a^{2}-u^{2}}}$ $u=t$ $a=1$