化简:1+sin4X-cos4X分之1+sin4X+cos4X
问题描述：
化简:1+sin4X-cos4X分之1+sin4X+cos4X
要写清楚,发20分的积分.
答
原式=(sin2x^2+cos2x^2+2sin2xcos2x+cos2x^2-sin2x^2)/(sin2x^2+cos2x^2+2sin2xcos2x-cos2x^2+sin2x^2) =(2cos2x^2+2sin2xcos2x)/(2sin2x^2+2sin2xcos2x) =[2(sin2x+cos2x)cos2x]/[2(sin2x+cos2x)sin2x] =cos2x/sin2...