化简两个不同角角的函数
Sin2A+sin2B-sin2A *sin2B+cos2A*cos2B (注"2"代表平方)
Sin2A+sin2B-sin2A *sin2B+cos2A*cos2B sin^2A+sin^2B-sin^2A*sin^2B+cos^2A*cos^2B =sin^2A*(1-sin^2B)+cos^2A*cos^2B+sin^2B =sin^2A*cos^2B+cos^2A*cos^2B+sin^2B =cos^2B*(sin^2A+cos^2A)+sin^2B =cos^2B+sin^2B =1
Sin^A+sin^B-sin^A *sin^B+cos^A*cos^B= (注"^"代表平方) Sin^A+sin^B(1-sin^A )+cos^A*cos^B= Sin^A+sin^B*cos^A +cos^A*cos^B= Sin^A+cos^A *(sin^B+cos^B)= Sin^A+cos^A *(sin^B+cos^B)= Sin^A+cos^A *1= Sin^A+cos^A =1
答:我的解答如下:详情>>
答:详情>>