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Im very confused on how to get the sides of the unit circle. By that i mean like sin/cos of 0,90,180,360... I can get the others by this logic for example:

Image: enter image description here

For example if it asks me

  1. Sin 150: I would first see the quadrant.. Its Quadrant II so it means Sin is the only one positive... Ok so i know its positive, and next i would know that sin is always the hieght so according to that picture it is 1/2.. So i would know the sin of 150 is 1/2...

I can do that for every angle presented on the picture exept the 0,90,180,360... How do you possible calculate the sin/cos for the angles i just mentioned. Thankyou

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  • $\begingroup$ The only way out of it i can guess is memorizing the pattern....??? @LuizCordeiro $\endgroup$ – amanuel2 Feb 29 '16 at 22:39
  • $\begingroup$ Im not memorizing all... Im just memorizing 0,90,180,360.... the others are easy to figure out.. And its just a pattern.. For cos in 0-360 it goes 1,0,-1,1 For sin 0,1,0,0 $\endgroup$ – amanuel2 Feb 29 '16 at 22:47
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In the following triangles, use the Pythagorean theorem to find the missing lengths, then find the trigonometric ratios for $0,\pi/2, \pi/3,\pi/4,$ and $\pi/6$. Don't even bother memorizing, just draw the appropriate triangle.

enter image description here

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  • $\begingroup$ What do you need the degenerated triangle for? $\endgroup$ – Surb Mar 1 '16 at 15:43
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    $\begingroup$ @Surb The degenerated triangle is for calculating $\sin 0$ and $\sin\pi/2$ ala opposite-adjacent-hypotenuse style. $\endgroup$ – John Joy Mar 1 '16 at 15:47
  • $\begingroup$ Dosent really matter know since i memorized pattern lol. But thanks for helpin me out $\endgroup$ – amanuel2 Mar 1 '16 at 23:59

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