(2x²y-2xy²)-[(-3x²y²+3x²y)+(3x²y²-3xy²)]其中x=-1y=2先化简,再求值
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![(2x²y-2xy²)-[(-3x²y²+3x²y)+(3x²y²-3xy²)]其中x=-1y=2先化简,再求值](/uploads/image/z/469585-1-5.jpg?t=%282x%26%23178%3By-2xy%26%23178%3B%29-%5B%28-3x%26%23178%3By%26%23178%3B%2B3x%26%23178%3By%29%2B%283x%26%23178%3By%26%23178%3B-3xy%26%23178%3B%29%5D%E5%85%B6%E4%B8%ADx%3D-1y%3D2%E5%85%88%E5%8C%96%E7%AE%80%2C%E5%86%8D%E6%B1%82%E5%80%BC)
(2x²y-2xy²)-[(-3x²y²+3x²y)+(3x²y²-3xy²)]其中x=-1y=2先化简,再求值
(2x²y-2xy²)-[(-3x²y²+3x²y)+(3x²y²-3xy²)]其中x=-1y=2
先化简,再求值
(2x²y-2xy²)-[(-3x²y²+3x²y)+(3x²y²-3xy²)]其中x=-1y=2先化简,再求值
原式=2x²y-2xy²-(-3x²y²+3x²y+3x²y²-3xy²)
=2x²y-2xy²-(3x²y-3xy²)
=2x²y-2xy²-3x²y+3xy²
=-x²y+xy²
=-2-4
=-6
(2x²y-2xy²)-[(-3x²y²+3x²y)+(3x²y²-3xy²)]
=2x^2y-2xy^2-(3x^2y-3xy^2)
=xy^2-x^2y
=xy(y-x)
=-1*2(2+1)
=-6
xy2-x2y =16