Đáp án:
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`a,`
`1/2x^2 . (-2x^2y^2z) . (-1)/3 x^2y^3`
`= [1/2 . (-2) . (-1/3)] (x^2 . x^2 . x^2) (y^2 . y^3) z`
`= 1/3 x^6 y^5 z`
Bậc : `6 + 5 + 1 = 12`
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`b,`
`(-x^2y)^3 . 1/2 x^2y^3 . (-2 xy^2z)^2`
`= -1 x^6 y^3 . 1/2 x^2y^3 . 4 x^2 y^4 z^2`
`= [-1 . 1/2 . 4] (x^6 . x^2 . x^2) (y^3 . y^3 . y^4) z^2`
`= -2 x^{10} y^{10} z^2`
Bậc : `10 + 10 + 2 = 22`
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`c,`
`(-6x^3 zy) (2/3 yx^2)^2`
`= -6 x^3yz . 4/9 x^4 y^2`
`= (-6 . 4/9) (x^3 . x^4) (y . y^2) z`
`= (-8)/3 x^7 y^3 z`
Bậc : `7 + 3 + 1 = 11`
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`d,`
`(xy - 5x^2y^2 + xy^2 - xy^2) - (x^2y^2 + 3xy^2 - 9x^2y)`
`= xy - 5x^2y^2 + xy^2 - xy^2 - x^2y^2 - 3xy^2 + 9x^2y`
`= xy + (-5x^2y^2 - x^2y^2) + (xy^2 - xy^2 - 3xy^2) + 9x^2y`
`= xy - 6x^2y^2 - 3xy^2 + 9x^2y`
Bậc : `4`
