Answer
$x^{4}+6x^{3}-11x^{2}-4x+3$
Work Step by Step
$ \begin{array}{lllllllll}
& & & & x^{2} & +6x & -4 & & (*)\\
& & & & x^{2} & -x & -2 & & \\
& & & -- & -- & -- & -- & & \\
& & & & -2x^{2} & -12x & +8 & ... & \leftarrow-2\times(*)\\
& & & -x^{3} & -6x^{2} & +4x & & ... & \leftarrow-x\times(*)\\
& & x^{4} & +6x^{3} & -4x^{2} & & & .. & \leftarrow x^{2}\times(*)\\
\hline & & & & & & & & \\
& & x^{4} & +5x^{3} & -12x^{2} & -8x & +8 & ... & \leftarrow combine
\end{array}$
