$\text{YeunhatbanT}$
Đáp án + Giải thích các bước giải:
`a, 2x^2- 5x + 3`
` =2x^2 - 2x - 3x + 3`
`=2x(x - 1) - 3(x - 1)`
`=(x - 1)(2x - 3)`
`b)3x^2 + 5x - 2`
`=3x^2 - x + 6x - 2`
`=x(3x - 1) + 2(3x - 1)`
`=(3x - 1)(x + 2)`
`c)15x^2 - x - 6`
`=15x^2 - 10x + 9x - 6`
`=5x(3x - 2) +3(3x- 2)`
`=(3x - 2)(5x +3)`
`d)x^2 - 4x + 13`
`=x^2 - 4x + 4 + 9 `
`=(x - 2)^2 + 3^3 + 2.(x - 2).3 - 2.(x - 2).3`
`=x - 2 + 3)^2 - 2.(x - 2).3`
`=(x + 1)^2 - 2.(x - 2).3`
`=(x + 1 - \sqrt{2.(x - 2).3})(x + 1 + \sqrt{2.(x - 2).3})`
`=(x + 1 - \sqrt{6.(x - 2)})(x + 1 + \sqrt{6(x - 2)})`