化简sin^2Xsin^2Y+cos^2Xcos^2Y-0.5cos2Xcos2Y

来源:学生作业帮助网 编辑:作业帮 时间:2024/11/16 07:34:55

化简sin^2Xsin^2Y+cos^2Xcos^2Y-0.5cos2Xcos2Y
化简sin^2Xsin^2Y+cos^2Xcos^2Y-0.5cos2Xcos2Y

化简sin^2Xsin^2Y+cos^2Xcos^2Y-0.5cos2Xcos2Y
(sinx)^2(siny)^2+(cosx)^2(cosy)^2-1/2*cos2xcos2y
=(1-cos2x)/2*(1-cos2y)/2+(1+cos2x)/2*(1+cos2y)/2-1/2*cos2xcos2y
=(1-cos2x-cos2y+cos2xcos2y)/4+(1+cos2x+cos2y+cos2xcos2y)/4-1/2*cos2xcos2y
=(1+cos2xcos2y)/2-1/2*cos2xcos2y
=1/2

= sin 2;x+sin 2;y-sin 2;xsin 2;y+1-sin 2;x-sin 2;y sin 2;xsin 2;y =1 Sin^2x Sin^2y-Sin^2xSin^2y+Cos^2xCos^2y =