a)
(x ²y ² – $\frac{1}{2}$ xy + 2xy ) (x – 2y)
b)
((x ² – xy + y ² ) (x + y)
a) (x ²y ² – $\frac{1}{2}$ xy + 2xy ) (x – 2y) b) ((x ² – xy + y ² ) (x + y)
By Margaret
By Margaret
a)
(x ²y ² – $\frac{1}{2}$ xy + 2xy ) (x – 2y)
b)
((x ² – xy + y ² ) (x + y)
Đáp án:
Giải thích các bước giải:
a) `(x^2 y^2 – 1/2 xy + 2xy ) (x – 2y)`
`=x^2 y^2 . x – x^2 y^2 . 2y – 1/2 xy . x – 1/2 xy . (- 2y) + 2xy . x – 2xy . 2y`
`=x^3 y^2 -2 x^2 y^3 -1/2 x^2 y+xy^2+2x^2 y-4xy^2`
`=x^3 y^2 -2 x^2 y^3+3/2 x^2 y-3xy^2`
b) `(x^2-xy+y^2)(x+y)`
`=x^2 . x+x^2 y-xy . x -xy .y+xy^2 +y^3`
`=x^3+x^2 y-x^2 y-xy^2+xy^2 +y^3`
`=x^3+y^3`
Đáp án:
`a)(x^2y^2-1/2xy+2xy)(x-2y)`
`=(x^2y^2+3/2xy)(x-2y)`
`=x^3y^2-2x^2y^3+3/2x^2y-3xy^2`
`b)(x^2-xy+y^2)(x+y)`
`=x^3+x^2y-x^2y-xy^2+xy^2+y^3`
`=x^3+y^3`.