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Easy trig question

  • Thread starter GreenPrint
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  • #1
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I feel kind of dumb asking this (it's been a while sense I took precalc) but I always thought that if I had something like

arctan(stuff) = answer
that if I added any whole integer multiple of 2pi to the answer I would get equivalent answers. Is this correct? Like
answer - 4pi = answer -2pi = answer + 2pi = answer + 4 pi

you get different angles but they can still act as correct answers to
arctan(stuff)?
 

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  • #2
SammyS
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I feel kind of dumb asking this (it's been a while sense I took precalc) but I always thought that if I had something like

arctan(stuff) = answer
that if I added any whole integer multiple of 2pi to the answer I would get equivalent answers. Is this correct? Like
answer - 4pi = answer -2pi = answer + 2pi = answer + 4 pi

you get different angles but they can still act as correct answers to
arctan(stuff)?
tan(x) is periodic with a period of π .

So if you have arctan(stuff) = answer , then adding any integer multiple of π to 'answer,' will give 'another answer'.

In other words, if tan('answer') = stuff, then it's also true that tan('another answer') = stuff .
 
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ok well in this case i can add multiples of two pi's as well than?
 
  • #4
SammyS
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ok well in this case i can add multiples of two pi's as well than?
Sure, since 2π is an integer multiple of π .
 

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