When two curves y = f(x) and y = g(x) intersect at x = a, x = c, and x = b (a < c < b), the total enclosed area is NOT simply |integral from a to b of (f - g) dx|. Instead, you must split: A = integral from a to c of |f(x) - g(x)| dx + integral from c to b of |f(x) - g(x)| dx. In each subinterval, determine which curve is on top and integrate accordingly. Example: y = sin(x) and y = cos(x) from 0 to pi. They cross at x = pi/4. From 0 to pi/4, cos(x) >= sin(x). From pi/4 to pi, sin(x) >= cos(x) (up to 5*pi/4, but we only go to pi). Compute each piece separately and add.