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sweetcandy01
how do you solve cos(2pi)? thanks in advance
Well there is a couple of ways to go about this problem. You could graph it or you could get an exact number. Try putting cos(2pi) into your calculator to get a decimal answer.
with a calculator, but people memorize the sin, cos and tan of "special" angles 2 pi is a special angle.
thanks for the responses! i thought there was a way to solve it by hand.. i'll just memorize it then!
Think graphically |dw:1371404215303:dw|
It comes back to 0 So its equivalent to cos 0
Well in a unit circle yes. Is that what the problem is asking for? Cosine is in the fourth quadrant, it is always positive in there. The coordinates of 2pi are on 0 degrees
cos2pi =cos360 =cos(90*4+0) = cos0 =1