Answer
$Q(x)=\displaystyle \frac{1}{3}x^{2}+\frac{1}{3}x+\frac{2}{3},\quad R(x)=-1$
Work Step by Step
$ \left.\begin{array}{l}
\\
3x+6\ )\\
\\
\\
\\
\\
\\
\\\\\\
\\
\end{array}\right. \begin{array}{rrrrrr}
\frac{1}{3}x^{2} & +\frac{1}{3}x & +\frac{2}{3} & & \\
\hline x^{3} & +3x^{2} & +4x & +3 & \\
x^{3} & +2x^{2} & & & \\
-- & -- & & & \\
& x^{2} & +4x & +3 & \\
& x^{2} & +2x & & \\
& -- & -- & & \\
& & 2x & +3 & \\
& & 2x & +4 & \\
& & -- & -- & \\
& & & -1 &
\end{array} $
$Q(x)=\displaystyle \frac{1}{3}x^{2}+\frac{1}{3}x+\frac{2}{3},\quad R(x)=-1$