Step 1:

\

The integral is $\"\"$ .

\

Rewrite the integral into two parts .

\

$\"\"$

\

Evaluate the first part.

\

$\"\"$

\

$\"\"$

\

Now consider the second part.

\

$\"\"$

\

Let $\"\"$ .

\

Since $\"\"$ , we can interpret this integral as the area under the curve $\"\"$ over the interval $\"\"$ .

\

Graph the function $\"\"$ .

\

$\"\"$

\

Apply squaring on each side.

\

$\"\"$

\

The graph shows that the $\"\"$ is the quarter-circle with radius $\"\"$ in figure.

\

Therefore

\

$\"\"$

\

$\"\"$ .

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$