c = a + b =

b = 0 (slider from 0 to 0.09, step 0.0010)
a = 1 (slider from -5 to 5, step 0.1)
φ(x) = 1 / sqrt(2 * 3.141592653589793) exp(-0.5 x^(2))
ab: a + b
text1: ab + ""
Φ = Integral(φ(x), -10, ab)