What is the frequency of #f(theta)= sin 6 t - cos 18 t #?

1 Answer
Dec 29, 2015

First find the period of each function ...

Explanation:

Period of #sin6t# is #(2pi)/6=(1/3)pi#

Period of #cos18t# is #(2pi)/18=(1/9)pi#

Next, find the smallest integer values for m and n, such that ...

#m(1/3)pi=n(1/9)pi# or #9m=3n#

This occurs when #n=3# and #m=1# , so the smallest combined period is #pi/3#

#pi/3~~1.047# radians

frequency = 1/period #=3/pi~~0.955#

hope that helped

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