Trigonometry

gimme5minutes

I'm revising some trigonometry here and I wanted to check my answers with you guys

Basically I have to give the period and amplitude of each function, here's the questions and my answers -

1). sin 3Θ -- amp 1, period 120

2). sin (3Θ-pi/6) -- amp 1, period 120

3). sin 3(Θ - pi/6) -- amp 1, period 120

4). cos 1/3Θ -- amp 1, period 1080

5). cos ((Θ+pi)/3), amp 1, period 1080

Is that correct? Cheers.

gimme5minutes

Can someone confirm if I have the above right?

Fremen

The first three are correct. The notation on the fourth is ambiguous: did you mean

1/(3Θ) or (1/3)Θ ?
If it's the latter, you're correct.
In the first case, there is no fixed amplitude.
see here:
http://www70.wolframalpha.com/input/?i=cos(1%2F(3x))

The link is worth a look, even if the question asked for cos(1/3)Θ.
This is an example of a bounded continuous function with no limit as x -> 0
Wolfram alpha might be useful for your LC, too.

The last one seems OK.

seandoiler

Fremen wrote: »

The first three are correct. The notation on the fourth is ambiguous: did you mean

1/(3Θ) or (1/3)Θ ?
If it's the latter, you're correct.
In the first case, there is no fixed amplitude.

just being a stickler but you meant to say period as opposed to amplitude in that sentence

Fremen

Yup