x^3 * (x^2+1)^(1/2) intergration help

[kpx001]

how would i approach this problem
x^3 * (x^2+1)^(1/2)

u sub and then x sub doesnt work. is it legal to do u = x^2 + 1 then (u-1)^(3/2) = (x^2)^(3/2) ?

 

[Deleted member 4993]

how would i approach this problem
x^3 * (x^2+1)^(1/2)

Try

\(\displaystyle x \, = \, \tan\theta\)

u sub and then x sub doesnt work. is it legal to do u = x^2 + 1 then (u-1)^(3/2) = (x^2)^(3/2) ?