MathDB
Today's calculation of Integral 622

Source:

July 1, 2010
calculusintegrationtrigonometrygeometryanalytic geometryfunctioncalculus computations

Problem Statement

For 0<k<20<k<2, consider two curves C1:y=sin2x (0xπ), C2:y=kcosx (0xπ).C_1: y=\sin 2x\ (0\leq x\leq \pi),\ C_2: y=k\cos x\ (0\leqq x\leqq \pi). Denote by S(k)S(k) the sum of the areas of four parts enclosed by C1, C2C_1,\ C_2 and two lines x=0, x=πx=0,\ x=\pi. Find the minimum value of S(k).S(k).
2010 Nagoya Institute of Technology entrance exam