find the length of the curve of r(t)=<2t, t^2, (t^3)/3>

so i take the derivative of each, and then square them and get

<4, 4t^2, t^4>

and the formula is srqt (4+4t^2+t^4)

and i need to find it from t=1 to t-2.

i just don't know how to solve that integral. it doesn't really seem possible. can anyone help with that? thanks