Using Archimedes' technique to find the area under a parabola. Convex Parabola, triangular area shaded green between points marked as A an x intercept (at x = -1), C the y intercept and B an x intecept (x = 1). Triangular area shaded purple between points A, G a point on the parabola where x = -1/2, and C. A third triangular area shaded purple between points C, I a point on the parabola where x = 1/2, and B. Segments of the region under the parabola shaded gold from point labelled as A, to point marked as G, from G to C and from C to I. These segments are the remaining regions after the triangles have been shaded.