求x-y 0.5siny=0所確定的函數微分和二階導數

z对x的偏导=cosx+cos(x+y)=0时,cosx=-cos(x+y)=cos(pi-x-y),所以x=pi-x-y.同理z对y的偏导=0时,有y=pi-x-y.所以x=y=pi/3.此时z=3

siny-e^x+xy^2=0cosy.y'-e^x+2xy.y'+y^2=0(cosy+2xy)y'=e^x-y^2y'=(e^x-y^2)/(cosy+2xy)

dy/dx=-x/siny-sinydy=xdx两边取积分cosy=ln|x|+c再问：详细些再答：囧算错了-sinydy=xdxS-sinydy=Sxdxcosy=x^2/2+c再问：要一步一步来再

两边对x求两次导数：1-y'+1/2cosyy'=0；==>y'=1/(1-cosy/2)0-y''+1/2(y'(-siny)+cosyy'')=0==>y''=y'siny/(cosy-2)再将y

两边微分cosydy=(dx+dy)/(x+y)[cosy(x+y)-1]dy=dxdy/dx=1/[cosy(x+y)-1]

cos(2x-2y)=cos2(x-y)=2cos^2(x-y)-1cos(x-y)=cosxcosy+sinxsiny(sinx+siny)^2=sin^2x+sin^2y+2sinxsiny=4/

x-y+1/2siny=0两边对x求导得1-y'+1/2cosy*y'=0y'=2/(2-cosy)y''=dy'/dx=(dy'/dy)*(dy/dx)=[-2/(2-cosy)²]*si

dsiny+de^x-dxy²=0cosydy+e^xdx-y²dx-2xydy=0cosydy-2xydy=y²dx-e^xdxdy/dx=(y²-e^x)/

siny+xe^y=0确定有隐函数：y=y(x)于是,同时在两边对x求导：(siny+xe^y)'=0'y'*cosy+e^y+xy'e^y=0y'*(cosy+xe^y)=-e^yy'=-e^y/(

变为dx/dy=-x+siny公式：对于y'=P(x)y+Q(x),通解为y=(∫{Q(x)e^[-∫P(x)dx]}dx+C)e^[∫P(x)dx]对于dx/dy=-x+siny,P(y)=-1,Q

siny+e^x=xy^2,两边求微分,cosydy+e^xdx=d(xy^2)cosydy+e^xdx=y^2dx+2xydy整理,得(e^x-y^2)dx=(2xy-cosy)dydy/dx=(e

两边对x求导有1-y'+y'cosy=0所以y'=1/(cosy-1)

隐函数求导,就是先左右一起求微分,加个d,然后写出多少dx+多少dy=0,移项变成dy/dx=多少的形式就好了

x-y+1/2siny=0F(x,y)=y-x-1/2siny=0F,Fx,Fy在定义域的任意点都是连续的,F(0,0)=0Fy(x,y)>0f'(x)=-Fx(x,y)/Fy(x,y)=1/(1-1

cos(x+y)cosy+sin(x+y)siny=cos((x+y)-y)=cosx=4/5sinx=正负3/5tanx=正负3/4

解两边求导y‘cosy+e^x-y^2-2xyy'=0即y’(cosy-2xy)=y^2-e^xy'=(y^2-e^x)/(cosy-2xy)或者F(x,y)=siny+e^x-xy^2=0Fx=e^

cos(x-y)=cosx*cosy+sinx*siny(sinx+siny)^2+(cosx+cosy)^2=1sinx^2+cos^2+siny^2+cosy^2+2sinx*siny+2cosx

x*e^y+siny=0e^y+x*e^y*y'+cosy*y'=0=>y'=-e^y/[xe^y+cosy]再问：你好！我数学太烂。。能不能补充一下完整的答案。。。再答：x*e^y+siny=0两边

sinx+siny=-sinzcosx+cosy=-cosz平方相加sin²x+cos²x+sin²y+cos²y+2(cosx+cosy+sinxsiny)=

这是隐函数的求导cosy*y'+3e^3x-6x^2y^2-4x^3*y*y'=0dy/dx=y'=(6x^2y^2-3e^3x)/(cosy-4x^3y)