VOLUMES OF SOLIDS
Shell Method
About y-axis
V = 2\pi \cdot radius \cdot height \cdot thickness
V = 2\pi \int_a^b [f(x) - g(x)]dx
About x = h \le a:
Radius = x - h
About x = h \ge b:
Radius = h - x
About x-axis
V = 2\pi \cdot radius \cdot height \cdot thickness
V = 2\pi \int_c^d [f(y) - g(y)]dy
About y = k \le c:
Radius = y - k
About y = k \ge d:
Radius = k - y