0 / | | x*cos(x) | -------- dx | 3 | sin (x) | / 0
Use integration by parts:
Let and let .
Then .
To find :
Let .
Then let and substitute :
The integral of is when :
Now substitute back in:
Now evaluate the sub-integral.
The integral of a constant times a function is the constant times the integral of the function:
Don't know the steps in finding this integral.
But the integral is
So, the result is:
Now simplify:
Add the constant of integration:
The answer is:
/ | | x*cos(x) x cos(x) | -------- dx = C - --------- - -------- | 3 2 2*sin(x) | sin (x) 2*sin (x) | /
Use the examples entering the upper and lower limits of integration.