# How do you use synthetic substitution to find f(3) and f(-4) for f(x)= x^4-8x-11?

f(3)= ${3}^{4} - 8 \cdot 3 - 11 = 81 - 24 - 11 = 46$
f(-4)= ${\left(- 4\right)}^{4} - 8 \left(- 4\right) - 11 = 256 + 32 - 11 = 277$