y\"+2y\'+y=x

x-y/x-x+y/y-(x+y)(x-y)/y²y/x=2x-y/x-x+y/y-(x+y)(x-y)/y²y/x=2x-y/x-x+y/y-(x+y)(x-y)/y²

y"+y''-2y=2xy"+y''-2y=2xy"+y''-2y=2xy"+y''-2y=2x先求y"+y''-2y=0的通r²+r-2=0,r=1或-2y=ce^x+de^(-2x)再求一个特解,

微分方程y"-2y''+y=x微分方程y"-2y''+y=x微分方程y"-2y''+y=x先求对应齐次方程的特征方程为r″-2r+1=0r1=r2=1齐次方程的通解为Y=e^x(C1+C2x)再求非其次方程

填空：x-y/x+y=()/x^2-y^2填空：x-y/x+y=()/x^2-y^2填空：x-y/x+y=()/x^2-y^2分子分母同时乘以x-y即(x-y)^2/(x+y)(x-y)=(x-y)^

（x-y)2•(y-x)³(x-y)=?（x-y)2•(y-x)³(x-y)=?（x-y)2•(y-x)³(x-y)=?答：（x-y)

(x-y)(x-2y)+(x+2y)(x-3y)-2(x-3y)(x-4y)=(x-y)(x-2y)+(x+2y)(x-3y)-2(x-3y)(x-4y)=(x-y)(x-2y)+(x+2y)(x-3

(x+y)(x-y)+(x-y)平方-(x-y)(3x-y)其中x=-2y=3分之一(x+y)(x-y)+(x-y)平方-(x-y)(3x-y)其中x=-2y=3分之一(x+y)(x-y)+(x-y)

已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y)已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y)已知x-y/x+y=3,求代数式5(x-y)/x+y

(x-4y)(2x+y)=(x-4y)(2x+y)=(x-4y)(2x+y)=：(x-4y)(2x+y)=2x^2+xy-8xy-4y^2=2x^2-7xy-4y^22x^2-8xy+xy-4y^2=

(x+y)(2x-3y)=?(x+y)(2x-3y)=?(x+y)(2x-3y)=?（x+y）（2x-3y）=2x-3xy+2xy-3y=2x-xy-3y

x+y>=2,x-yx+y>=2,x-yx+y>=2,x-y由题意的x≥2-yx≤2+y∴2-y≤x≤2+y4-2y≤2x≤4+2y4-3y≤2x-y≤4+y∵0≤y≤3∴-3≤-y≤0-9≤-3y≤

x+y>=2,x-yx+y>=2,x-yx+y>=2,x-y根据线性条件画出可行域,X+Y≥2,X-Y≤2,0≤Y≤3.画出可行域后,再画出直线2x-y=0然后平移,就可求得Z的最大值和最小值,m=2

y''-2y=(e^x)-xy''-2y=(e^x)-xy''-2y=(e^x)-x首先求齐次方程通y''-2y=0特征方程：x-2=0x=2为特征根∴y=Ce^(2x)设方程的一个特解为y=Ae^x+ax+

y''+2y/x=x通解y''+2y/x=x通解y''+2y/x=x通解

dy/dx=(2x*x*x*y-y*y*y*y)/(x*x*x*x-2x*y*y*y)dy/dx=(2x*x*x*y-y*y*y*y)/(x*x*x*x-2x*y*y*y)dy/dx=(2x*x*x*

【2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2】/2(x-y)^2=【2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2】/2(x-y)^2=【2(x-y)^3-8(

（x-y)(x+y)-(x+y)^2+2y(y-x),其中x=1,y=3.（x-y)(x+y)-(x+y)^2+2y(y-x),其中x=1,y=3.（x-y)(x+y)-(x+y)^2+2y(y-x)

2y(x+二分之一y)-[(x+y)(x-y)+2y(y+x)],其中|x-1|=22y(x+二分之一y)-[(x+y)(x-y)+2y(y+x)],其中|x-1|=22y(x+二分之一y)-[(x+

已知x-y=3,求[（x+y)(x-y)-(x-y)^2+2y(x-y)]除以的值已知x-y=3,求[（x+y)(x-y)-(x-y)^2+2y(x-y)]除以的值已知x-y=3,求[（x+y)(x-

已知3x=2y求x/x+y+y/x-y-y²/x²-y²已知3x=2y求x/x+y+y/x-y-y²/x²-y²已知3x=2y求x/x+y+