Question

Thực hiện phép tính 
1) (x-y).(6x²-4y²+\(\dfrac{1}{2}\)xy)
2) (6x-1).(3+x)+(2x+5).(-3x)

Answer 1

`1)(x-y)(6x^2-4y^2+1/2xy)`

`=6x^3-4xy^2+1/2x^2y-6x^2y+4y^3-1/2xy^2`

`=6x^3-11/2x^2y-9/2xy^2+4y^3`

`2)(6x-1)(3+x)+(2x+5)(-3x)`

`=18+6x^2-x-3-6x^2-15x`

`=-15x+15`

Answer 2

1)\(\left(x-y\right)\left(6x^2-4y^2+\dfrac{1}{2}xy\right)=6x^3+4y^3-\dfrac{9}{2}xy^2-\dfrac{11}{2}x^2y\)

2)\(\left(6x-1\right)\left(3+x\right)+\left(2x+5\right)\left(-3x\right)=\left(6x^2+17x-3\right)+\left(-6x^2-15x\right)=2x-3\)

tick mik nha

Answer 3

2: Ta có: \(\left(6x-1\right)\left(x+3\right)+\left(-3x\right)\left(2x+5\right)\)

\(=6x^2+18x-x-3-6x^2-15x\)

\(=2x-3\)