how do you integrate from 1 to -2? Shouldn't it be from -2 to 1?

Question

slaaibak · Answer

With that argument, we can also ask why integrate from 1 to 2.

We take the area from 0 to 2, then we subtract the area from 0-1, giving the area from 1-2.

anonymous · Answer

okay, so i understand how do integrate when limits are in ascending order, but i don't get how to integrate when the limits are in descending order. would i just take the integral from -2 to 0 and then from 0 to 1?

zarkon · Answer

$$\int\limits_{b}^{a}f(x)dx=-\int\limits_{a}^{b}f(x)dx$$

anonymous · Answer

Zarkon, so then is the area under f(x) negative or the area under f'(x)?