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Periodicity help

Hi, how could I find the period for each of these



1) x(t) = 8 sin 2t

Period = 2pi/ absolute 2 = pi ???

2 ) x(t) = 8 sin ^2(t)
3) x(t) = 8 sin 2t
4) x(t) = 2 |cos t|
Reply 1
BUMP
Reply 2
Well the period is the measure of how often it repeats. sin2t \sin 2t has a period of π \pi since it's a stretch parallel to x axis scale factor 0.5 right , so the curve is 'squashed'. For the second one if you're having trouble use the identity cos2t=12sin2t \cos 2t = 1-2\sin^2 t and it should be a bit easier.
For the fourth one try sketching the curve.
Reply 3
Original post by B_9710
Well the period is the measure of how often it repeats. sin2t \sin 2t has a period of π \pi since it's a stretch parallel to x axis scale factor 0.5 right , so the curve is 'squashed'. For the second one if you're having trouble use the identity cos2t=12sin2t \cos 2t = 1-2\sin^2 t and it should be a bit easier.
For the fourth one try sketching the curve.


Cheers! :biggrin:

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