Step-by-step explanation:
ok ? what is the problem ?
f(-3) means that x = -3.
so, we need to put -3 in place of every x in the function expression and simply calculate ...
f(-3) = (-3)² + 2(-3)² - 11 = 9 + 2×9 - 11 = 27 - 11 = 16
now, I suspect you made a typo, because in your function expression you have 2 terms with x².
i think the first one was originally a x³.
then the result would be
f(-3) = (-3)³ + 2(-3)² - 11 = -27 + 2×9 - 11 = -27 + 18 - 11 =
= -20
