Question

What is the period of `f(t)=cos 9 t`?

Answer 1

Period `=(2pi)/abs(9)=(2pi)/9`

Explanation:

from the equation `y=a cos bx`

the formula for period `= (2pi)/abs(b)`

from the given `f(t)=cos 9t`

`a=1` and `b=9`

period `=(2pi)/abs(9)=(2pi)/9`

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