Let u=sin(2x),so du =2cos(2x dx x u

Letu=sin(2x),sodu=2cos(2x)dx. Whenx=0,u=0; whenx= π 4,u=1. Thus, Rπ/4 0 cos(2x)sin(sin(2x))dx= R1 0 sinu1 2 du = 1 2 [−cosu]1 0 = ... ................
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