Final answer:
For the function f(a)=3^a and an input of a=-3, the output is 1/27.
Step-by-step explanation:
When evaluating the function f(a)=3^a with the input a=-3, we apply the concept of negative exponents. According to the rules of exponents, a negative exponent indicates that the base should be in the denominator and the exponent made positive. Therefore:
f(-3) = 3^{-3} = 1 / 3^3 = 1 / (3×3×3) = 1 / 27
Thus, the output of the function for the input -3 is 1/27 when expressed as a fraction.