what kind of hocus pocus witchcraft is this

>>8548362
I have no idea what that is, but it looks like those two integrals on the right are just the expansion of that first one.

Sums of integrals are integrals right?

This is complex analysis im guessing?

>>8548362
>extremely elementary algebraic manipulation
>le hokus pokus xD

if x is nonpositive then |x|=?

[math] \int_{-b}^{-a} g(|x|)\,dx = \int_{a}^b g(x)\,dx [/math]

for 0<a<b

>>8548362
Looks at where the integrals start.

|x| = -x if x < 0
= x if x > 0.

So -a|x| = -a(-x) = ax if x < 0
-a|x| = -ax if x < 0