Answer
$g$ is exponential, $f$ is not.
$g(x)=3(2^{x})$
Work Step by Step
Exponential models have form: $y=Ab^{x}$
When $x$ increases by one unit, the value of$ f$ is multiplied by $b.$
$A=f(0)$
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When x changes from 1 to 2, f is halved,
but, when it changes from -1 to 0, it is not halved.
A b described above does not exist, f is not exponential.
When $x$ increases by one unit,
the value of $ g$ is doubled (multiplied by $b=2$), so $g$ is exponential.
since $A=g(0)=3,$ the exponential model is $g(x)=3(2^{x})$
