Need with this problem, 16 points for it.

Let f(x) = ak^x  

f(0) = 1 = a  

f(5) = 4 = k^5  

k = 4^(1/5)  

f(x) = 4^(x/5) = 2^(2x/5)  

Exponential function

Hope this helps :)

5+2x=a

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