y=2x^2-3x+7,求y.y=cos(3x+1)求y就2题,懂的答

y =(cos^2) x - sin (3^x),求y' Sin x-sin y=2/3 cos x-cos y=1/2 求cos(x-y) sin(x+y)sin(x-y)=k,求cos^2x-cos^2y 5cos(x-y/2)+7cos(y/2)=0求tan(x/2)*tan[(x-y)/2] 当cos^2x-cos^2y=√3/2时,求sin(x+y）×sin(x-y) y=(cos^2x) 求dy y=cos^3(2x)+e^x求导数 y=2^sinx + cos√x 求y’ 已知sinx=3/5,x∈(π/2,π),求【sin(x+y)+sin(x-y)】/【cos（x+y）+cos（x-y）】的值 du(x,y)=2xycos(x^2y)dx+x^2cos(x^y)dy,求u(x,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=2x^2-3x+7,求y.y=cos(3x+1)求y就2题,懂的答 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) 求微分 y=ln(1-x^2) y=e^-x +cos(3+x) y=sin2x 已知：2x+y=6,x-3y=1 求7y(x-3y)(x-3y)-2(3y-x)(3y-x) 8y^3+sin2y+x^3+sinx=0求Cos(x+2y) cos(2x+y)=3cosy,求tanx*tan(x+y)