y = 5 cos 3x,y = 5 − 5 cos 3x,0 ≤ x ≤ π/3求范围内两个方程式组成的面积

已知sinx=3/5,x∈(π/2,π),求【sin(x+y)+sin(x-y)】/【cos（x+y）+cos（x-y）】的值 y=sinx+cos^5 x,求y’ ：y' +y= cos x y= 若cos（x+y)=4/5,cos(x-y)=-4/5,且90 cos(x+y)=1/5,cos(x-y)=3/5则tanx.tany=?帮我解 cos(x+y)=1/5,cos(x-y)=3/5则tanx.tany=?帮我解题 若cos(x+y)=4/5,cos(x-y)=-4/5,且3π/2 已知cos(x+y)=1/3,cos(x-y)=1/5,求tanx×tany的值 COS(X加Y)＝3/5,cos(x减y)=4/5.则tanx乘tany 5cos(x-y/2)+7cos(y/2)=0求tan(x/2)*tan[(x-y)/2] 求y=sin^5x ,y=cos(4x+3) 的导数, 已知sin(x-y)cosx-cos(x-y)sinx=3/5求tan2y的值 最近没有认真听数学已知x,y为锐角,cos（x+y)=12/13,cos(2x+y)=3/5,则cosx的值为? y =(cos^2) x - sin (3^x),求y' 若cos(x+y)cos(x-y)=1/3,则cos^x-sin^y=?^为平方 Sin x-sin y=2/3 cos x-cos y=1/2 求cos(x-y) 6-4x-x^2=5/|sin(y/x)cos(y/x)|的解 求解微分方程y+y=cos x