Prove that $$( f ( x ) \cdot g ( x ) ) \cdot h ( x ) = f ( x ) \cdot ( g ( x ) \cdot h ( x ) )$$ for all linear polynomials $f ( x )$ and $g ( x )$ and $h ( x )$.
Prove that
$$( f ( x ) \cdot g ( x ) ) \cdot h ( x ) = f ( x ) \cdot ( g ( x ) \cdot h ( x ) )$$
for all linear polynomials $f ( x )$ and $g ( x )$ and $h ( x )$.