y = 1 - x², y = 0
x = -1, x = 1
y = x², y = 0
x = 0, x = 2
S= ∫^(1) _(-1)(1-x^2)dx=2 ∫ ^(1)_(0)(1-x^2)dx=2(x-(x^3/3))|^(1)_(0)=
=2*(1-(1/3)=2*(2/3)=4/3
2.
S= ∫ ^(2)_(0)x^2dx=(x^3/3)|^(2)_(0)=8/3