Find the area of the region inside: r = 9 sinθ but outside: r = 1
is a circle with center at (0, 4/2) and radius 4/2 while r= 1 is a circle with center at (0, 0) and radius 1.
The two curves intersect where [/tex]r= 1= 9 sin(\theta)[/tex] or . For , that is satified by and .
For between those two limits, r ranges from 1 up to . The "differential of area" in polar coordinates is so the area is given by .