Answer:
see below
Step-by-step explanation:
Well there are two main reasons
1. exponential functions don't have a negative value, i mean
[tex]f(x)\neq -something[/tex]
2. well exponential functions are like a curve, the firsts values are very close to each other, but then they start jumping like mad (translate it to your own words), for example in
[tex]f(x) = x^2[/tex]
the first positive values are
1,2,9 but then 16,25,36,49