若sinx*siny=1 则sin(x+y)=?

证明sin(x+y)sin(x-y)=sinx-siny 求函数z=sinx+siny+sin(x+y)(0 求sin(x+y)=sinx+siny的导数 证明 [sin(2x+y)/sinx]-2cos(x+y)=siny/sinx 求证：sin(2x+y)/sinx-2cos(x+y)=siny/sinx 证明sinx+siny+sinz-sin(x+y+z)=4sin((x+y)/2)sin((x+y)/2)sin((x+ sinx+siny=-1/3 cosx+cosy=1/2,求sin(x+y)的值. 证明sin(x+y)sin(x-y)=（sinx）^2-(siny）^2. 求下列导数：sin(x+y)=sinx+siny e^x+x=e^y+y 证明cosx(cosx-cosy)+sinx(sinx-siny)=2sin(x-y)/2 已知sinx+siny=1/3,cosx-cosy=1/5,求cos(x+y),sin(x-y). 已知sinx-siny=1/2,cosx-cosy=1/2,x、y均为锐角,求sin(x-y)