已知丨a+2丨+(b+1)²+(c-1/3)²=0,求代数式5abc-{2a²b-[3abc-(4ab²-a²b)]}
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![已知丨a+2丨+(b+1)²+(c-1/3)²=0,求代数式5abc-{2a²b-[3abc-(4ab²-a²b)]}](/uploads/image/z/8780130-18-0.jpg?t=%E5%B7%B2%E7%9F%A5%E4%B8%A8a%2B2%E4%B8%A8%2B%EF%BC%88b%2B1%EF%BC%89%26%23178%3B%2B%EF%BC%88c-1%2F3%EF%BC%89%26%23178%3B%3D0%2C%E6%B1%82%E4%BB%A3%E6%95%B0%E5%BC%8F5abc-%EF%BD%9B2a%26%23178%3Bb-%5B3abc-%284ab%26%23178%3B-a%26%23178%3Bb%29%5D%EF%BD%9D)
已知丨a+2丨+(b+1)²+(c-1/3)²=0,求代数式5abc-{2a²b-[3abc-(4ab²-a²b)]}
已知丨a+2丨+(b+1)²+(c-1/3)²=0,求代数式5abc-{2a²b-[3abc-(4ab²-a²b)]}
已知丨a+2丨+(b+1)²+(c-1/3)²=0,求代数式5abc-{2a²b-[3abc-(4ab²-a²b)]}
∵丨a+2丨+(b+1)²+(c-1/3)²=0
∴a+2=0 b+1=0 c-1/3=0
a=-2 b=-1 c=1/3
∴5abc-{2a²b-[3abc-(4ab²-a²b)]}
=5abc-2a²b+3abc-4ab²+a²b
=8abc-a²b-4ab²
=8*(-2)*(1/3)-(-2)²*(-1)-4*(-2)*(-1)²
=-16/3+4+8
=20/3
∵丨a+2丨+(b+1)²+(c-1/3)²=0
∴丨a+2丨≥0,(b+1)²≥0,(c-1/3)²≥0
∵丨a+2丨=0,(b+1)²=0,(c-1/3)²=0
∴a=-2,b=-1,c=1/3
原式=5abc-{2a²b-[3abc-4ab...
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∵丨a+2丨+(b+1)²+(c-1/3)²=0
∴丨a+2丨≥0,(b+1)²≥0,(c-1/3)²≥0
∵丨a+2丨=0,(b+1)²=0,(c-1/3)²=0
∴a=-2,b=-1,c=1/3
原式=5abc-{2a²b-[3abc-4ab²+a²b)}
=5abc-{2a²b-3abc+4ab²-a²b}
=5abc-2a²b+3abc-4ab²+a²b
=(5+3)abc+(1-4-2)ab²
=8abc-5ab²
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