pi -- 2 / | | x*cos(x) | -------- dx | 2 | / -pi ---- 2
Integral((x*cos(x))/2, (x, -pi/2, pi/2))
The integral of a constant times a function is the constant times the integral of the function:
Use integration by parts:
Let and let .
Then .
To find :
The integral of cosine is sine:
Now evaluate the sub-integral.
The integral of sine is negative cosine:
So, the result is:
Add the constant of integration:
The answer is:
/ | | x*cos(x) cos(x) x*sin(x) | -------- dx = C + ------ + -------- | 2 2 2 | /
Use the examples entering the upper and lower limits of integration.