f(x) = x + 1
g(x) = x^(2) - (2 * x) + 1
A, B = Intersect(f, g)
h(x) = If[0 ≤ x ≤ 3, f(x)]
p(x) = If[0 ≤ x ≤ 3, g(x)]
a = Surface(p, 45, xAxis)
b = Surface(h, 45, xAxis)