`a,` `2x^2yz . ( -3xy^3z )`
`= [ 2 . ( -3 ) ] . ( x^2yz . xy^3z )`
`= -6x^3y^4z^2`
`Bậc` `:` `9`
`b,` `( -12xyz ) . ( -4/3x^2 yz^3 )y`
`= (-12xyz) × (-4/3x^2 y^2z^3)`
`= [ -12 . ( -4/3 ) ] . ( xyz . x^2 y^2z^3 )`
`= -16x^3y^3z^5`
`Bậc` `:` `11`
`HỌC` `TỐT` `NHA` `!`
`#NOCOPY`