Final answer:
The range of the function f(x) = 3 + 9 is 12.
Step-by-step explanation:
The given function is f(x) = 3 + 9 which simplifies to f(x) = 12.
The range of a function represents all the possible y-values that the function can take. In this case, since f(x) is always equal to 12, the range of the function is just the single value 12.
Therefore, the range of f(x) = 3 + 9 is 12.
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