Toán Thực hiện phép nhân (2x-1)^2 – 3(x-1)(x+2) – (x-3)^2 04/12/2021 By Parker Thực hiện phép nhân (2x-1)^2 – 3(x-1)(x+2) – (x-3)^2
`(2x-1)^2-3(x-1)(x+2)-(x-3)^2` `=(2x)^2-2.2x.1+1^2-3(x^2+2x-x-2)-(x^2-2.x.3+3^2)` `=4x^2-4x+1-3x^2-3x+6-x^2+6x-9` `=(4x^2-3x^2-x^2)+(-4x-3x+6x)+(1+6-9)` `=-x-2` Trả lời
`\text{~~Holi~~}` `(2x-1)^2-3(x-1)(x+2)-(x-3)^2` `= 4x^2-4x+1+(-3x+3)(x+2)-(x^2-6x+9)` `= 4x^2-4x+1-3x^2-6x+3x+6-x^2+6x-9` `= 0-x-2` `= -x-2` Trả lời
`(2x-1)^2-3(x-1)(x+2)-(x-3)^2`
`=(2x)^2-2.2x.1+1^2-3(x^2+2x-x-2)-(x^2-2.x.3+3^2)`
`=4x^2-4x+1-3x^2-3x+6-x^2+6x-9`
`=(4x^2-3x^2-x^2)+(-4x-3x+6x)+(1+6-9)`
`=-x-2`
`\text{~~Holi~~}`
`(2x-1)^2-3(x-1)(x+2)-(x-3)^2`
`= 4x^2-4x+1+(-3x+3)(x+2)-(x^2-6x+9)`
`= 4x^2-4x+1-3x^2-6x+3x+6-x^2+6x-9`
`= 0-x-2`
`= -x-2`