已知x²y=3,求2xy(x^5y^2-3X^3y-4x)的值

已知x²y=3,求2xy(x^5y^2-3X^3y-4x)的值
已知x²y=3,求2xy(x^5y^2-3X^3y-4x)的值

已知x²y=3,求2xy(x^5y^2-3X^3y-4x)的值
2xy(x^5y^2-3X^3y-4x)
=2x^6y^3-6x^4y^2-8x^2y^2
=2(x²y)³-6（x²y)²-8x²y
=2x3³-6x3²-8x3
=54-54-24
=-24
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2xy(x^5y^2-3x^3y-4x)
=2x^6y^3-6x^4y^2-8x^2y
=2(x²y)³-6(x²y)²-8x²y
=2×3³-6×3²-8×3
=54-54-24
=-24能回答详细点吗？请把所以过程说出来，这样我才会采纳这样写就可以了，这样还不够详细就真不明白你所说的“...

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2xy(x^5y^2-3x^3y-4x)
=2x^6y^3-6x^4y^2-8x^2y
=2(x²y)³-6(x²y)²-8x²y
=2×3³-6×3²-8×3
=54-54-24
=-24

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