\(\dfrac{x^3+x^2-12}{x-2}=\dfrac{x^3-2x^2+3x^2-12}{x-2}\)
\(=\dfrac{x^2\left(x-2\right)}{x-2}+\dfrac{3\left(x-2\right)\left(x+2\right)}{x-2}\)
=x^2+3x+6
=>Chọn C
`(x^3+x^2-12):(x-2)`
`x^3+x^2` `-12` ``| `x-2`
`-``x^3-2x^2` `x^2+3x+6`
_______________
`3x^2` `-12`
`-` `3x^2-6x`
_______________
`6x-12`
`-` `6x-12`
__________
`0`
`->C`