Answer:
f(7) = f(1) + 24
Explanation:
from f(7) = f(6) + 4
we can observe that any term is basically the previous term in the progression plus 4 which means:
f(6) = f(5) + 4
f(5) = f(4) + 4
f(4) = f(3) + 4
f(3) = f(2) + 4
f(2) = f(1) + 4
If we start substituting the lower terms into next highest term, starting from the bottom and working our way up, we will get:
f(3) = f(2) + 4 = [ f(1) + 4 ] + 4 = f(1) + 8
f(4) = f(3) + 4 = f(1) + 8 + 4 = f(1) + 12
f(5) = f(4) + 4 = f(1) + 12 + 4 = f(1) +16
f(6) = f(5) + 4 = f(1) + 16 + 4 = f(1) + 20
f(7) = f(6) + 4 = f(1) + 20 + 4 = f(1) + 24