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¡Òsinxsin2xsin3xdx RT

sinxsin3x=-(cos4x-cos2x)/2¡Òsinxsin2xsin3xdx=(1/4)¡Òsin4xdx - (1/2)¡Òsin2xcos4xdx=-(1/16)cos4x - (1/4)¡Òcos4xd(...


ÈçºÎÇóº¯Êý f(x) = sinx + sin2x + sin3x µÄÖµÓò...

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