已知非零有理数x,y满足x²-4xy+4y²=0,求x-y/x+y-y-x/x+y的值.
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![已知非零有理数x,y满足x²-4xy+4y²=0,求x-y/x+y-y-x/x+y的值.](/uploads/image/z/2575569-57-9.jpg?t=%E5%B7%B2%E7%9F%A5%E9%9D%9E%E9%9B%B6%E6%9C%89%E7%90%86%E6%95%B0x%2Cy%E6%BB%A1%E8%B6%B3x%26%23178%3B-4xy%2B4y%26%23178%3B%3D0%2C%E6%B1%82x-y%2Fx%2By-y-x%2Fx%2By%E7%9A%84%E5%80%BC.)
已知非零有理数x,y满足x²-4xy+4y²=0,求x-y/x+y-y-x/x+y的值.
已知非零有理数x,y满足x²-4xy+4y²=0,求x-y/x+y-y-x/x+y的值.
已知非零有理数x,y满足x²-4xy+4y²=0,求x-y/x+y-y-x/x+y的值.
x²-4xy+4y²=0
(x-2y)²=0
x-2y=0
x=2y
于是
(x-y)/(x+y)-(y-x)/(x+y)
=[(x-y)-(y-x)]/(x+y)
=2x/(x+y)
=2*2y/(2y+y)
=4y/3y
=4/3
x²-4xy+4y²=0
即(x-2y)²=0
∴x=2y
x-y/x+y=y/3y=1/3
x²-4xy+4y²=0
x-2y=0
x=2y
代入后面所要求的式子,即可
主要是你这里没有括号,我不能确定