If f is a function satisfying `f(x+y)=f(x)f(y)`for all `x ,y in X`such that `f(1)=3`and `sum_(x=1)^nf(x)=120`, find the value of n.

Explanation

To solve the problem, we start with the function \( f \) that satisfies the property:

\[ f(x+y) = f(x)f(y) \]

for all \( x, y \) in the domain \( X \). We are also given that \( f(1) = 3 \) and that the sum \( \sum_{x=1}^{n} f(x) = 120 \). We need to find the value of \( n \).

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