Compute
![\[ \int_0^{-1} (x+1)^2 \, dx. \]](https://www.stumblingrobot.com/wp-content/ql-cache/quicklatex.com-27c72cbe63d9668255f64ae490196b66_l3.png "Rendered by QuickLaTeX.com")
Since we computed 
in the previous exercise, we apply the theorem on expansion/contraction of the interval of integral (Theorem 1.19 in Apostol) with constant 
to obtain,
![\[ \int_0^{-1} (x+1)^2 \, dx = - \int_{-1}^0 (x+1)^2 \, dx = -\frac{1}{3}. \]](https://www.stumblingrobot.com/wp-content/ql-cache/quicklatex.com-b70e146c67c69890cf8e4ffe657badd7_l3.png "Rendered by QuickLaTeX.com")
Compute
Since we computed in the previous exercise, we apply the theorem on expansion/contraction of the interval of integral (Theorem 1.19 in Apostol) with constant to obtain,
I don’t see why this is an application of theorem 1.19.