∫(4,-2)f(x)dx
= -∫(-2,4)f(x)dx
= -∫(-2,0)f(x)dx - ∫(0,4)f(x)dx
=-∫(-2,0)e^(-x)dx - ∫(0,4)e^x dx
=-[-e^(-x)] | (-2,0) - e^x | [0,4]
=-e^4-e^2+2
∫(4,-2)f(x)dx
= -∫(-2,4)f(x)dx
= -∫(-2,0)f(x)dx - ∫(0,4)f(x)dx
=-∫(-2,0)e^(-x)dx - ∫(0,4)e^x dx
=-[-e^(-x)] | (-2,0) - e^x | [0,4]
=-e^4-e^2+2