Answer
$-1$
Work Step by Step
Recall:
$\lim _{x\rightarrow a}p\left( x\right) =p\left( a\right)$
Thus,
$\lim _{x\rightarrow 1}\left( 5x^{4}-3x^{2}+6x-9\right)
\\=5\times 1^{4}-3\times 1^{2}+6\times 1-9
\\=5\times 1 -3 \times 1 + 6\times 1 - 9
\\=5-3+6-9
\\=2+6-9
\\=8-9
\\=-1$
