What is the period of #f(t)=sin( t / 7 )+ cos( (t)/21 ) #?

2 Answers
Leland Adriano Alejandro
Jan 23, 2016

Period#=42pi#

Explanation:

#p_1=(2pi)/(1/7)=14pi#

#p_2=(2pi)/(1/21)=42pi#

the period for the sum is the # lcm(14pi, 42pi)=42pi#

Ken Rubenstein
Jan 23, 2016

nice Leland!...it's the same as a polyrhythm in music....LCMs are SO important!! If one musician is playing in one meter and a second musician is playing in another meter, you can manipulate all manner of LCMs for the sake of polyrhythms.

Here is a pretty TI screenshot to support the results.

enter image source here

Related questions
See all questions in Amplitude, Period and Frequency
Impact of this question
1808 views around the world
You can reuse this answer
Creative Commons License