The integral function is
.
Let
.
Apply derivative on each side with respect to
.



Substitute
and
in the integral function.

Let
.
Apply derivative on each side with respect to
.


Substitute
and
in the integral function.

Trignometric substitution
.


Double angle formula :
.





Consider
.
For a right triangle,
and
.


.
.
Substitute corresponding values in the equation
.

Substitute
in above equation.

Substitute
in above equation.

.
.