Calculate the area of the region limited by curves:

1) $\displaystyle y=x^3$ and $\displaystyle y=x^2+2x$

answer: $\displaystyle \frac{37}{12}$

2) $\displaystyle y=x^3-2x^2-5x+6$, the axis-x, $\displaystyle x=-1$ and $\displaystyle x=2$

answer: $\displaystyle \frac{157}{12}$