Given the following functions below,

Factorising the denominators of both functions,
Factorising the denominator of f(x),

Factorising the denominator of g(x),

Multiplying both functions,
Since the argument of the sine function is x without any scaling factor, the period is 2π, the 1st selection.
Answer:
5
Step-by-step explanation: 3x5=15
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