y)=2xy

xy'+y=-xy^2的通解y'为一次导?xy'/y^2+1/y=-x-x(1/y)'+1/y=-x1/y=t-xt'+t=-x(t'x-t)/x^2=1/x(t/x)'=1/xt/x=lnx+ct=xlnx+cx1/y=xlnx+cxy=

（2xy-y)-(-y+xy)=    （2xy-y)-(-y+xy)=2xy-y+y-xy=2xy-xy-y+y=xy

xy'=y+xy的xdy=(y+xy)dxdy/y=((1+x)/x)dxln|y|=ln|x|+x+cy=±e^(ln|x|+x+c)其中c是常数

[-xy^2(2x+y)-8xy)-x^2y)]除以2xy=计算原式=(-2x²y²-xy³-8xy-x²y)÷2xy=-2x²y²÷2xy-xy³÷2xy-8xy÷2x

已知x+y=1,xy=-2,则x²y+xy²-2xyx²y+xy²-2xy=xy(x+y-2)=-2*(1-2)=2

已知xy^2=-2,求-xy（x^2y^5-xy^3-y)的值.-xy（x^2y^5-xy^3-y)=-(xy^2)^3+(xy^2)^2+xy^2=-(-2)^3+4-2=8+4-2=10

已知xy^2=-2求-xy(x^2y^5-xy^3-y)原式=-xy²（x²y^4-xy²-1）∵xy²=-2原式=2（（-2)²-（-2）-1）=10

已知xy^2=-2xy(x^2y^5-xy^3-y)xy(x^2y^5-xy^3-y)=xy^2(x^2y^4-xy^2-1)=(xy^2)[(xy^2)^2-(xy^2)-1]=-2×[(-2)²-(-2)-1]=-10

已知x-xy=8,xy-y=-9,求x+y-2xy的值x-xy=8(1)xy-y=-9(2)则有(1)-(2):X-XY-XY+Y=X+Y-2XY=8-(-9)=17

1-2/x+y=xy,4y+6x=xy.求xy的解?1-(2/x)+y=4y+6x1-(2/x)=3y+6x(x-2)/x=3y+6xx-2=3xy+6x²x-2-6x²=3xyxy=(x-2-6x²)/3

xy^2-e^x+e^y=1求y'是xy^2不是xy

y/x=ln(xy)求dy/dx(xy-y^2)/(xy+x^2)两边求导(y'x-y)/x^2=(y+xy')/xyxy+x^2y'=xyy'+y^2y'=(xy-y^2)/(xy+x^2)

xy^2=-3,求-xy(x^2y^5-xy^3-y)原式=-x³y^6+x²y^4+xy²=-(xy²)³+(xy²)²+xy²=-(-27)+9-3=33

当x-y=2xy时,求4x-3xy-4y/xy当x-y=2xy时,4x-3xy-4y/xy=4(x-y)-3xy/xy=8xy-3xy/xy=5xy/xy=5（4x-3xy-4y）/xy=4（x-y）/xy-3=5

()*3xy=6x^2y+2xy^22x+2/3y希望给奖励值啦

2xy+5y^2+()=x^2+3xyx^2+xy-5y^22xy+5y^2+()=x^2+3xy()=x^2+3xy-2xy-5y^2()=x^2+xy-5y^2()中填x^2+xy-5y^2

_____/xy=2y/2xy²填空分式1/xy=2y/2xy²填空分式【1】/xy=2y/2xy²填写的数=xy×2y÷2xy²=2xy²÷2xy²=1很高兴为您解答，祝你学习进

()-(x^2+3xy)=-xy-1/3y^2()-(x^2+3xy)=-xy-1/3y^2()=(x^2+3xy)+(-xy-1/3y^2)()=x^2+3xy-xy-1/3y^2=x^2-2xy-1/3y^2所以括号里写x^2-2xy-

可分离变量的微分方程:y'-xy^2=2xy..dy/dx=x(2y+y^2)dy/(2y+y^2)=xdx0.5dy[1/y-1/(y+2)]=xdx等式两边同时积分ln|y|-ln|y+2|=2Sxdxln|y|-ln|y+2|=x^2

（-3x^y+2xy)-()=4x^+xy(-3x^y+2xy)-(4x^+xy)=-3x^y+2xy-4x^-xy=-3x^y+xy-4x^所以填上-3x^y+xy-4x^等比a3²=a1a4(a1+2d)²=a1(a