设cos(x+y)sinx-sin(x+y)cosx=12／13 ,且y是第四象限角,则tany／2的值是A±2／3 B±3／2 C-3／2 D-2／3

化简sin(x+y)sinx+cos(x+y)cosx 化简sin(x+y)sinx+cos(x+y)cosx等于? 化简cos(x+y)sinx-sin(x+y)cosx sin(2x+y)/sinx-2cos(x+y) 化简 化简cos(x+y)sinx-sin(x+y)cosx sinx*sin(x+y)+cosx*cos(x+y)等于? cos（x+y）sinx-sin（x+y）cosx y= sin x cos x+sinx+cosx的值域 证明 [sin(2x+y)/sinx]-2cos(x+y)=siny/sinx 求证sin（2x+y)/sinx-2cos(x+y)=siny/sinx 求证：sin(2x+y)/sinx-2cos(x+y)=siny/sinx 为什么设y *＝A cos x +B sin x 证明sinx+cos(x+y)siny/cosx-sin(x+y)siny=tan(x+y) 答案:设1小于等于COSx-SINx小于等于根号2,则函数y=1-cos x+sin x+sinx cosx的值域为? 设0≤x≤π/2,求cos（sinx）＞sin（cos） 曲线Y= sin x 1_________ - __ 求导?sin x +cos x 2sinx /(sinx +cosx ) - 1/2 请问怎么证明sinX+sin(X+Y)+sin(X+2Y)/cosX+cos(X+Y)+cos(X+2Y)=tan(X+Y), 方程y^sinx=〖(sinx)〗^y确定y是x的函数,求y’x写出sin cos