Đáp án+Giải thích các bước giải:
`a)(6x^2+13x-5):(2x+5)`
`=\frac{6x^2+13x-5}{2x+5}`
`=\frac{6x^2+15x-2x-5}{2x+5}`
`=\frac{3x(2x+5)-(2x+5)}{2x+5}`
`=\frac{(2x+5)(3x-1)}{2x+5}`
`=3x-1`
`b)(x^3-3x^2+x-3):(x-3)`
`=\frac{x^3-3x^2+x-3}{x-3}`
`=\frac{x^2(x-3)+(x-3)}{x-3}`
`=\frac{(x-3)(x^2+1)}{x-3}`
`=x^2+1`
`c)(2x^4+x^3-5x^2-3x-3):(x^2-3)`
`=\frac{2x^4+x^3-5x^2-3x-3}{x^2-3}`
`=\frac{2x^4-6x^2+x^3-3x+x^2-3}{x^2-3}`
`=\frac{2x^2(x^2-3)+x(x^2-3)+(x^2-3)}{x^2-3}`
`=\frac{(x^2-3)(2x^2+x+1)}{x^2-3}`
`=2x^2+x+1`