y=x²+2/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

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)

y=x^2-2x（xy=x^2-2x（xy=x^2-2x（xf(x)=y=x^2-2x由反函数定义将x、y的位置互调一下x=y^2-2yx=(y-1)^2-1又∵x＜0∴反函数为f^-1(x)=y=-

y=x^2+2x(xy=x^2+2x(xy=x^2+2x(xy=x²+2xy+1=x²+2x+1=(x+1)²根号(y+1)=|x+1|因为x

3^x+2x=y,x3^x+2x=y,x3^x+2x=y,x

(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

x²-(x-2y)(x+2y)+(x²-y)(y+x²)=?x²-(x-2y)(x+2y)+(x²-y)(y+x²)=?x²-(x

(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*

4x方y/(x-2y)(x+2y)怎么算[x方/x-2y]-4x方y/(x-2y)(x+2y)=?4x方y/(x-2y)(x+2y)怎么算[x方/x-2y]-4x方y/(x-2y)(x+2y)=?4x

已知x+y=a,2x-y=-2a,求[（x/y-y/x)/(x+y)-x(1/x-1/y)]/[(x+1)/y]的值已知x+y=a,2x-y=-2a,求[（x/y-y/x)/(x+y)-x(1/x-1

若2/x-1/y=3,求[y/x-y/x-y(x-y/x-x+y)]/x-2y/x的值若2/x-1/y=3,求[y/x-y/x-y(x-y/x-x+y)]/x-2y/x的值若2/x-1/y=3,求[y