ysin3x-cos(y-x)=5 y=f(x) 求dy/dx

ysin3x-cos(y-x)=5 y=f(x) 求dy/dx ：y' +y= cos x y= 求解微分方程y+y=cos x cos(x)看到这个 cos(x)－cos(y)=? 证明COS（X+Y）COS（X-Y）=COS^2X-SIN^2Y 证明cos(x+y)cos(x-y)= cos^2(x)-sin^2(y) y=sinx+cos^5 x,求y’ 解微分方程y'=y/x+cos(y/x) 解微分方程y'=y/x+cos(y/x) y=cos(x+y) y对x的导数y=cos（x+y) y对x的导数 若cos（x+y)=4/5,cos(x-y)=-4/5,且90 求解微分方程y'*cos(y)=x+1-sin(y) 5cos(x-y/2)+7cos(y/2)=0求tan(x/2)*tan[(x-y)/2] y=2cos x (sin x+cos x) 解微分方程：y` cos y =(1+cos x sin y)sin y. y=(sin x + COS x)^2 sin(x+y)sin(x-y)=k,求cos^2x-cos^2y y=(cos x-2)/(cos x-1)的值域