giai cho mik bài này

Bài 9
$\displaystyle  \begin{array}{{>{\displaystyle}l}}
a.\ x^{5} +3x^{4} -2x^{2} -2x^{4} +1-x=\left( x^{5} +3x^{4} -2x^{2} -2x^{4}\right) +( 1-x)\\
b.x^{5} +3x^{4} -2x^{2} -2x^{4} +1-x=\left( x^{5} +3x^{4} -2x^{2} -2x^{4}\right) -( x-1)
\end{array}$
Bài 10: 
$\displaystyle  \begin{array}{{>{\displaystyle}l}}
a.\ 4x^{5} +x^{4} -3x^{2} -4x^{4} +5+x=\ 4x^{5} -3x^{4} -3x^{2} +5+x\\
=\ \left( 4x^{5} -3x^{4} -3x^{2}\right) +( 5+x)\\
b.\ 4x^{5} +x^{4} -3x^{2} -4x^{4} +5+x=\ 4x^{5} -3x^{4} -3x^{2} +5+x\\
=\ \left( 4x^{5} -3x^{4} -3x^{2}\right) -( -5-x)
\end{array}$