已知x²+4y²-4x+4y+5=0,求2x²+xy-y²分之x的4次方-y的4次方×xy-y²分之2x-y÷(y分之x²+y²)²的值.
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![已知x²+4y²-4x+4y+5=0,求2x²+xy-y²分之x的4次方-y的4次方×xy-y²分之2x-y÷(y分之x²+y²)²的值.](/uploads/image/z/5467410-18-0.jpg?t=%E5%B7%B2%E7%9F%A5x%26%23178%3B%2B4y%26%23178%3B-4x%2B4y%2B5%3D0%2C%E6%B1%822x%26%23178%3B%2Bxy-y%26%23178%3B%E5%88%86%E4%B9%8Bx%E7%9A%844%E6%AC%A1%E6%96%B9-y%E7%9A%844%E6%AC%A1%E6%96%B9%C3%97xy-y%26%23178%3B%E5%88%86%E4%B9%8B2x-y%C3%B7%EF%BC%88y%E5%88%86%E4%B9%8Bx%26%23178%3B%2By%26%23178%3B%EF%BC%89%26%23178%3B%E7%9A%84%E5%80%BC.)
已知x²+4y²-4x+4y+5=0,求2x²+xy-y²分之x的4次方-y的4次方×xy-y²分之2x-y÷(y分之x²+y²)²的值.
已知x²+4y²-4x+4y+5=0,求2x²+xy-y²分之x的4次方-y的4次方×xy-y²分之2x-y÷(y分之x²+y²)²的值.
已知x²+4y²-4x+4y+5=0,求2x²+xy-y²分之x的4次方-y的4次方×xy-y²分之2x-y÷(y分之x²+y²)²的值.
由第一个式子,配方就可以得到(x-2)²+(2y+1)²=0,因为平方数都不小于0,所以两个平方都为0
所以x=2,y=-1/2,然后再代入所求式子就可以得到答案