(a)
\The integral is
.
From the table of integrals Formula 89:
.

.
(b)
\The integral is
.
Find the integral using integration by parts.
\Integration by parts :
.
Consider
and
.
Consider
.
Consider
.
Apply integral on each side.
\
.
Substitute corresponding values in
.
.
(a)
.
(b)
.