1 / | | x*cos(x + 3) dx | / 0
Integral(x*cos(x + 3), (x, 0, 1))
Use integration by parts:
Let and let .
Then .
To find :
Let .
Then let and substitute :
The integral of cosine is sine:
Now substitute back in:
Now evaluate the sub-integral.
Let .
Then let and substitute :
The integral of sine is negative cosine:
Now substitute back in:
Add the constant of integration:
The answer is:
/ | | x*cos(x + 3) dx = C + x*sin(3 + x) + cos(3 + x) | /
-cos(3) + cos(4) + sin(4)
=
-cos(3) + cos(4) + sin(4)
-cos(3) + cos(4) + sin(4)
Use the examples entering the upper and lower limits of integration.