Answer:
f(1) = a + b + c + d
f(2) = 8a + 4b + 2c + d
f(3) = 27a + 9b + 3c + d
f(4) = 64a + 16b + 4c + d
f(5) = 125a + 25b + 5c + d
f(6) = 216a + 36b + 6c + d
Explanation:
For these problems, subsititue the number in the x position in f(x) in for the x in the equation.
For example for f(2)
f(2) =

f(2) = 8a + 4b + 2c + d