Do I have memorize the entire Unit circle ?

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majormuss
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Do I have memorize the entire Unit circle ??

Homework Statement



I am currently takin a trig class and I was a bit daunted by the Unit Circle and all its special angles. My question is... Do I haveto memorize the entire Unit Circle and its angles?? Will it be given to me during exams(as cheat sheet)??

Homework Equations





The Attempt at a Solution

 
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You'd have to ask your teacher that. Common angles you might be expected to know without a cheat sheet are 0, pi/6 (30 deg), pi/4 (45 deg), pi/3 (60 deg), pi/2 (90 deg). That's not too much, and you would only need to know them for sine and cosine. Probably, you can use triangles to remember them more easily. Just knowing these means you know the analogous angles in the other quadrants too.
 


It's good to.

We had to, but I took a college class. It's not as hard as it looks- memorize thetas first- they're easy once you see the pattern- then when you see the pattern it will be really easy to memorize. =)
 


I agree with Tedjn, and if you consider that 0° and 90° are pretty trivial (sine and cosine are either 0 or 1, as is easily seen by looking at a unit circle), then there are only 3 angles (30°, 45°, 60°) whose sine and cosine need to be memorized. This involves remembering 3 numbers:

[tex]\frac{\sqrt{1}}{2}, \ \frac{\sqrt{2}}{2}, \ \frac{\sqrt{3}}{2}[/tex]​

Obviously the square-root sign is not necessary for the first one, but I included it as it may make this sequence of numbers easier to memorize.
 


Yeah, it's a good idea. It will make your math life easier.
 


thanks... i'll try to incorporate your suggestions!
 


One thing that helped me to understand it better was when I realized it's basically just one quadrant folded over onto itself twice.
 


shelovesmath said:
One thing that helped me to understand it better was when I realized it's basically just one quadrant folded over onto itself twice.

That's really true. Just learn one of them, and you'll be on your way. :wink: