Tính: $-\frac{5}{2}(xy)^{2}.x^{3}+\frac{3}{y}(2x)^{3}(\frac{y}{2}xy)^{2}-\frac{1}{3}x.3x^{4}y^{2}$
2 câu trả lời
Giải thích các bước giải:
`-5/2(xy)^2 . x^3 + 3/y(2x)^3(y/2xy)^2 - 1/3x . 3x^4y^2`
`= -5/2x^5y^2 + 3/y . 8x^3 . (y^2)/4 . x^2y^2 - x^5y^2`
`= -5/2x^5y^2 + 3/4y . 8x^3 . x^2y^2 - x^5y^2`
`= -5/2x^5y^2 + 6x^5y^3 - x^5y^2`
`= x^5y^2(-5/2 + 6y - 1)`
`= x^5y^2(6y - 7/2)`
`-5/2(xy)^2 . x^3 + 3/y(2x)^3(y/2xy)^2 - 1/3x . 3x^4y^2`
`= -5/2x^5y^2 + 3/y . 8x^3 . (y^2)/4 . x^2y^2 - x^5y^2`
`= -5/2x^5y^2 + 6x^5y^3 - x^5y^2`
`= (-5/2 + 6y - 1)x^5y^2`
`= [6y - (-5/2 + 1)]x^5y^2`
`= (6y - 7/2)x^5y^2`
