已知|x-1|+(y-1)^+0.求代数式(x^2+4xy-2y^2)-(x^2+y)-1/2(x-8y^2)的值!能快就快,
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![已知|x-1|+(y-1)^+0.求代数式(x^2+4xy-2y^2)-(x^2+y)-1/2(x-8y^2)的值!能快就快,](/uploads/image/z/12058156-28-6.jpg?t=%E5%B7%B2%E7%9F%A5%7Cx-1%7C%2B%EF%BC%88y-1%29%5E%2B0.%E6%B1%82%E4%BB%A3%E6%95%B0%E5%BC%8F%28x%5E2%2B4xy-2y%5E2%29-%28x%5E2%2By%29-1%2F2%28x-8y%5E2%29%E7%9A%84%E5%80%BC%21%E8%83%BD%E5%BF%AB%E5%B0%B1%E5%BF%AB%2C)
已知|x-1|+(y-1)^+0.求代数式(x^2+4xy-2y^2)-(x^2+y)-1/2(x-8y^2)的值!能快就快,
已知|x-1|+(y-1)^+0.求代数式(x^2+4xy-2y^2)-(x^2+y)-1/2(x-8y^2)的值!
能快就快,
已知|x-1|+(y-1)^+0.求代数式(x^2+4xy-2y^2)-(x^2+y)-1/2(x-8y^2)的值!能快就快,
绝对值和"平方大于等于0,相加等于0,若有一个大于0,则另一个小于0,不成立.
所以两个都等于0
所以x-1=0,y-1=0
x=1,y=1
所以(x^2+4xy-2y^2)-(x^2+y)-1/2(x-8y^2)
=x^2+4xy-2y^2-x^2-y-1/2x+4y^2
=4xy+2y^2-y-1/2x
=4+2-1-1/2
=9/2