The answer is [tex]f(3)=3,408.[/tex]
To solve this problem, just plug [tex]3[/tex] into the function and simplify.
[tex]f(x) = 5x^6 - 3x^5 + 6x^4 +6 \\
f(3) = 5(3)^6 - 3(3)^5 + 6(3)^4 +6 \\
= 5(729) - 3(243) + 6(81) + 6 \\
= 3645 - 729 + 486 + 6 \\
= 3408
[/tex]