I know that $\displaystyle Si(x)=\int_0^{x}\frac{sin(t)}{t}dt$. I can't see how this helps!!$\displaystyle I(x):=\frac{1}{6}\int_{2x^3}^{3x^2} \frac{sin(t)}{t}dt$ for $\displaystyle 0<x<\frac{3}{2}.$

Integration by parts isn't useful either as it makes an infinitely long sequence.

Macluarin expansions also don't help. They make something very messy.

gah!!