1/x-1/y=1/(x+y)
(y-x)/xy=1/(x+y)
(y-x)(y+x)=xy
y²-x²=xy
(y²-x²)²=(xy)²
(y^4)-2(xy)²+(x^4)=(xy)²
(x^4)+(y^4)=3(xy)²
((x^4)+(y^4))/((xy)²)=3
x^2/y^2+y^2/x^2=((x^4)+(y^4))/((xy)²)=3
已知1/x-1/y=1/(x+y),则x^2/y^2+y^2/x^2的值.
2个回答
相关问题
-
已知x=3/2,y=1/2则x(x-y)^2-y(y-x)^2的值为
-
已知y=x-1，则（x-y）2+（y-x）+1的值为______．
-
已知x=y,则下列各式:x-2=y-2; 2x=3y; -x=-y; x/y =1 (x-1)/2=(y-1)/2; x
-
已知：x+y=1,xy=-1/2,则x(x+y)(x-y)-x(x+y)^2=
-
已知：x+y=1,xy=-1/2,求：(x+y)²(x-y)+2y²(x+y)的值.
-
1.已知x:y=2:3,且2x+y/2-1=x-y/3,求x,y的值.2.已知x,y的值满足等式x+1/2=y+3/4=
-
已知y=√(1-8x)+√(8x-1)+1/2,求代数式√(x/y+y/x+2)-√(x/y+y/x-2)的值
-
已知实数x、y满足（x2+y2）（x2+y2-1）=2，则x2+y2的值为______．
-
已知x,y属于R,满足2≤y≤4-x,x≥1,则x^2+y^2+2x-2y+2/xy-x+y-1的最大值
-
已知x，y∈R，满足2≤y≤4-x，x≥1，则x2+y2+2x−2y+2xy−x+y−1的最大值为______．