- #1
mushroomyo
- 1
- 0
hi, I am trying to find the integral of x^3sqrt(1+x^4)dx
i set it up like this:
u=x^3 dv=sqrt(1+x^4)
du = 3x^2dx v=2/3(1+x^4)^(3/2)
and using uv-integralvdu i get
(2/3x^3(1+x^4)^3/2) - 2/3integral((1+x^4)^(3/2)3x^2)dx
i know that in the end, the integral should equal 1/6(x^4+1)^(3/2) but i don't know how to get there from where i stopped...
help?
i set it up like this:
u=x^3 dv=sqrt(1+x^4)
du = 3x^2dx v=2/3(1+x^4)^(3/2)
and using uv-integralvdu i get
(2/3x^3(1+x^4)^3/2) - 2/3integral((1+x^4)^(3/2)3x^2)dx
i know that in the end, the integral should equal 1/6(x^4+1)^(3/2) but i don't know how to get there from where i stopped...
help?