>>11236355or you could just think about it. The area in the middle = blue curve integral (middle)- orange curve integral (middle)
The area on the sides = orange curve integral (sides)- blue curve integral (sides).
Subtract both areas and see if they equal zero:
area in the middle - area on the side= blue curve integral (middle) + blue curve integral (sides) - orange curve integral (middle) - orange curve integral (sides)
Thus it's literally just the integral of blue minus the integral of orange.
Since they are normalized Gaussians, both the integrals are 1. So 1-1 = 0
