求齐次方程xy'-y-根号下(y^2-x^2)=0的通解,我算出来的答案是y=sin(C...
解:设y=xu,原方程化成(x^2)u-|x|根号下(u^2-1)=0,分离变量可解得 ln|u+根号下(u^2-1)|=ln|x|+ln|c|,即u+根号下(u^2-1)=cx,回代得y+根号下(y^2-x^2)=cx^2。说明:这是同济大学《高等数学(第六版)》上册中习题7-3(309页)的第1(1)题的原题。
求齐次方程xy'-y-√(y^2-x^2)=0的通解
解:∵xy'-y-√(y-x)=0 ==>y'-y\/x-√(y\/x-1)=0 ∴设y=xt,则y'=xt'+t 代入方程得xt'-√(t-1)=0 ==>dt\/√(t-1)=dx\/x ==>ln(t+√(t-1))=ln│x│+ln│C│ (C是积分常数)==>t+√(t-1)=Cx ==>y\/x+√(y\/x-1)=Cx ==>y+√(y-x)=Cx 故原方程...
求齐次方程xy'-y-√(y^2-x^2)=0的通解
解:∵xy'-y-√(y-x)=0 ==>y'-y\/x-√(y\/x-1)=0 ∴设y=xt,则y'=xt'+t 代入方程得xt'-√(t-1)=0 ==>dt\/√(t-1)=dx\/x ==>ln(t+√(t-1))=ln│x│+ln│C│ (C是积分常数)==>t+√(t-1)=Cx ==>y\/x+√(y\/x-1)=Cx ==>y+√(y-x)=Cx 故原方程...
求xy'-y-√(x^2+y^2)=0的通解,请写过程,方法越简单越好
dy\/dx=y\/x+√[1+(y\/x)^2]令u=y\/x,则y=xudy\/dx=u+xdu\/dx∴u+xdu\/dx=u+√(1+u^2)∴xdu\/dx=√(1+u^2)∴du\/√(1+u^2)=dx\/x∴ln[u+√(1+u^2)]=lnx+C1∴u+√(1+u^2)=Cx【其中C=e^C1】√(1+u^2)=Cx-u∴1+u^2=(Cx)^2+u^2-2Cxu∴1=(Cx)^2-2Cy∴通解为(...
1.微分方程xy'-y-√y^2-x^2=0的通解为?2.设y=arctan(e^x)-ln√(e^2...
xy'-y-√(y^2-x^2)=0 (xy'-y)\/x^2=√(y^2-x^2)\/x^2 d(y\/x)=√[(y\/x)^2-1]dx\/x secu=y\/x dsecu\/tanu=dln|x| secudu=dln|x| dln|secu+tanu|=dln|x| secu+tanu=Cx 通解y\/x+√((y\/x)^2-1)=Cx 2 y'=e^x\/(1+e^2x) -2e^2x\/(1+e^2x)^2 *(1\/2...
xy'-y-√(y^2-x^2)=0的通解让x\/y=u,得到y'=u+√u^2-1 在这我有一个小...
设y=ux,则dy=xdu+udx,∴dy\/dx=xdu\/dx+u,原方程变为xdu\/dx-√(u^-1)=0,分离变量得du\/√(u^-1)=dx\/x,∴ln[u+√(u^-1)]=lnx+lnc,∴u+√(u^-1)=cx,∴y+√(y^-x^)=cx^,√(y^-x^)=cx^-y,平方得y^-x^=(cx^)^-2cx^y+y^,∴y=(c\/2)x^+1\/(2c).与您...
求齐次方程xy'-y-√(y^2-x^2)=0,我想问这个求解的时候分x>0和x<0...
需要分类讨论的,两种情况结果是不一样的
微分方程xy'-y-根号下(x^2+y^2)=0的通解。
积分得:exp(r)=-exp(C*(1-sinθ))r=C\/(1-sinθ) (C为常量)sinθ=y\/r ,r=sqrt(x^2+y^2)化会直角坐标系 sqrt(x^2+y^2) = C\/(1-y\/sqrt(x^2+y^2))即 sqrt(x^2+y^2) -y =C 在计算过程中,可能舍掉了一些解,也可能多求了一些解,还得再仔细算算 ...
求微分方程xy'-y-√y2-x2=0的通解 √是根号
t dy\/dx=sect+x*sect tant dt\/dx x(sect+x*sect tant dt\/dx)-x sec t- x tan t =0 x*sect dt\/dx-1=0 dt\/dx =1\/x sec t sec t dt =dx\/x 积分得到 ln |sec t +tan t| = ln x +C'y \/ x + 根号((y\/x)^2 -1) =C x or y+根号(y^2-x^2)=C x^2 ...
xy'-y-√(x^2+y^2)=0的通解
解:∵xy'-y-√(x²+y²)=0 ==>xy'-y=√(x²+y²)==>√(1+(y\/x)²)\/x=(xy'-y)\/x²==>√(1+(y\/x)²)\/x=d(y\/x)\/dx ==>dx\/x=d(y\/x)\/√(1+(y\/x)²)==>ln│x│=arctan(y\/x)+ln│C│ (C是积分常数)==>...