Answer
a. $f(x)=a^{x}\qquad (a>$0, $ a\neq$1)
b. $f(x)=3^{x}$
Work Step by Step
The exponential function $f$ with base $a$ (where $a>0,\ a\neq 1$) is defined for all real numbers $x$ by
$f(x)=a^{x}$
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a. $f(x)=a^{x}\qquad (a>$0, $ a\neq$1)
b. $f(x)=3^{x}$