若|x-2|与(y+1/2)²互为相反数,试求代数式x²y-3xy²-1/3(3x²y-2 xy²)的值
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![若|x-2|与(y+1/2)²互为相反数,试求代数式x²y-3xy²-1/3(3x²y-2 xy²)的值](/uploads/image/z/952138-10-8.jpg?t=%E8%8B%A5%7Cx-2%7C%E4%B8%8E%EF%BC%88y%2B1%2F2%EF%BC%89%26%23178%3B%E4%BA%92%E4%B8%BA%E7%9B%B8%E5%8F%8D%E6%95%B0%2C%E8%AF%95%E6%B1%82%E4%BB%A3%E6%95%B0%E5%BC%8Fx%26%23178%3By-3xy%26%23178%3B-1%2F3%EF%BC%883x%26%23178%3By-2+xy%26%23178%3B%EF%BC%89%E7%9A%84%E5%80%BC)
若|x-2|与(y+1/2)²互为相反数,试求代数式x²y-3xy²-1/3(3x²y-2 xy²)的值
若|x-2|与(y+1/2)²互为相反数,试求代数式x²y-3xy²-1/3(3x²y-2 xy²)的值
若|x-2|与(y+1/2)²互为相反数,试求代数式x²y-3xy²-1/3(3x²y-2 xy²)的值
|x-2|与(y+1/2)²互为相反数
|x-2|+(y+1/2)²=0
x=2 y=-1/2
x²y-3xy²-1/3(3x²y-2 xy²)
=x²y-3xy²-3x²y+2 xy²/3
=-2x²y-7 xy²/3
=-2*2^2*(-1/2)-7*2*(-1/2)^2/3
=4-7/6
=17/6