# How do you evaluate the function f (x) = 4 • 7^x for x = -1 and x = 2?

Given f(x)=4·7^x
For $x = - 1$ we have f(-1)=4·7^(-1)=4/7 using ${a}^{- n} = \frac{1}{a} ^ n$
For x=2, we have f(2)=4·7^2=196