Answer
$x^{4}+6x^{3}-11x^{2}-4x+3$
Work Step by Step
$ \begin{array}{lllllllll}
& & & & x^{2} & +7x & -3 & & (*)\\
& & & & x^{2} & -x & -1 & & \\
& & & -- & -- & -- & -- & & \\
& & & & -x^{2} & -7x & +3 & ... & \leftarrow-1\times(*)\\
& & & -x^{3} & -7x^{2} & +3x & & ... & \leftarrow-x\times(*)\\
& & x^{4} & +7x^{3} & -3x^{2} & & & .. & \leftarrow x^{2}\times(*)\\
\hline & & & & & & & & \\
& & x^{4} & +6x^{3} & -11x^{2} & -4x & +3 & ... & \leftarrow combine
\end{array}$