(x 2y)dx (2x y)dy积分的值与路径无关
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解析2xdx+ydx+xdy+3y²dy=0(2x+y)dx+(x+3y²)dy=0(2x+y)dx=-(x+3y²)dydy/dx=(2x+y)/-(x+3y²
x^2*dy/dx=xy-y^2dy/dx=y/x-y^2/x^2u=y/xy=xuy'=u+xu'代入:u+xu'=u+u^2xu'=u^2du/u^2=dx/x-1/u=lnx+lnCCx=e^(
分离得到:dy/y=2xdx两边积分:ln|y|=x^2+C1y=±e^c1 *e^x^2 =Ce^x^2 (C =±e^c1) 图片如下
令z=1/x,则dx=-x²dz代入原方程得(x²y³+xy)dy=-x²dz==>dz/dy+y/x=-y³==>dz/dy+yz=-y³
对方程取导数y+x(dy/dx)+(dy/dx)=0(dy/dx)(x+1)=-ydy/dx=(-y)/(x+1)
先求解dy/dx=2xy,得到:dy/y=2xdx,所以ln|y|=x^2+c,即y=Cexp(x^2),其中C为常数,此时再用常数变易法,设y=C(x)exp(x^2),代入原式可得C(x)=C0-
先求dy/dx+2xy=0的解:dy/y=-2xdx,--->lny=-x^2+C=-ln(e^(x^2))+lnC=ln(C*e^(-x^2)),即y=C*e^(-x^2).然后令y=C(x)*e^
答:dy/dx=1+x+y^2+xy^2y'=(1+x)(1+y^2)y'/(1+y^2)=1+x(arctany)'=1+x积分得:arctany=x+x²/2+Cy=tan(x+x
直接分离变量就可以了dx/x=2ydylnx=y^2+C即x=C1*e^(y^2)
令y/x=u,dy=u+xdu,原方程化为:u+xdu/dx=x/(u^2)+u,即du/dx=1/(u^2)通解为:y=x*[(3x+3c)^(1/3)]
∵dy/dx=(x+y^3)/(xy^2)==>xy^2dy=(x+y^3)dx==>y^2dy/x^3=dx/x^3+y^3dx/x^4(等式两端同除x^4)==>d(y^3)/(3x^3)+y^3
y^2=(xy-x^2)dy/dxy^2/x^2=(y/x-1)dy/dxy/x=udy=udx+xduu^2=(u-1)(u-xdu/dx)u^2/(u-1)=u-xdu/dxxdu/dx=u-u^
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
分离变量经济数学团队为你解答,有不清楚请追问.请及时评价.再问:图片看不见啊再答:我再发一次再答:
三种方法1式中同时对x求导-(y+xy‘)cosxy+2yy'=0解出y’2式中同时取微分d{sin(xy)+y^2-e^2}=dsin(xy)+dy^2-de^2=-cosxydxy+2ydy=-c
你好!两边对x求导:e^(xy)*(y+xy')-y^2=y'cosy解得y'=(y^2-ye^(xy))/(xe^(xy)-cosy)
dx/dy-3xy=xy^2dx/x=(y^2+3y)dy两边积分得:lnx=y^3/3+3y^2/2+c==>x=exp(y^3/3+3y^2/2+c)=Cexp(y^3/3+3y^2/2)C常数
令y=xuy'=u+xu'代入方程:u+xu'=u^2/(u-1)xu'=u/(u-1)du(u-1)/u=dx/xdu(1-1/u)=dx/x积分;u-ln|u|=ln|x|+C1e^u/u=Cxe
你要求什么?
dy/dx=xy²+3xydy/dx=x(y²+3y)∫1/[y(y+3)]dy=∫xdx(1/3)∫(3+y-y)/[y(y+3)]dy=∫xdx∫[1/y-1/(y+3)]dy