2x^2y(-2xy^2)^3+(2xy)^3乘(-xy^2)^2,其中x=4 y=1/4 化简求值

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2x^2y(-2xy^2)^3+(2xy)^3乘(-xy^2)^2,其中x=4 y=1/4 化简求值
2x^2y(-2xy^2)^3+(2xy)^3乘(-xy^2)^2,其中x=4 y=1/4 化简求值

2x^2y(-2xy^2)^3+(2xy)^3乘(-xy^2)^2,其中x=4 y=1/4 化简求值
2x^2y(-2xy^2)^3+(2xy)^3乘(-xy^2)^2
=2x^2y×(-8x^3y^6) +8x^3y^3 ×x^2y^4
=-18x^5y^7 +8x^^5y^7
=-10x^5y^7
当x=4,y=1/4时
原式
=-10×4^5×(1/4)^7
=-5/8

(1)
2x^2y(-2xy^2)^3+(2xy)^3(-xy^2)^2
=-2x^2y(2xy^2)^3+(2xy)^3(xy^2)^2
=-16x^5y^7+8x^5y7
=-8x^5y^7
=-8*3^5*(1/4)^7
=-2*(3/4)^5

(2)
(1/3xy)^2(xy(2x-y)-2x(xy-y^2))

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(1)
2x^2y(-2xy^2)^3+(2xy)^3(-xy^2)^2
=-2x^2y(2xy^2)^3+(2xy)^3(xy^2)^2
=-16x^5y^7+8x^5y7
=-8x^5y^7
=-8*3^5*(1/4)^7
=-2*(3/4)^5

(2)
(1/3xy)^2(xy(2x-y)-2x(xy-y^2))
=(1/3xy)^2(xy(2x-y)-2xy(x-y))
=(1/3xy)^2(xy(2x-y-2x+2y))
=(1/3xy)^2(xy^2)
=(x^3y^4)/3
=(-27/8*16)/3
=-18
以上回答你满意么?

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