How do you find the value of cos 2π?

1 Answer
Oct 2, 2015

You get #cos(2pi)=1#

Explanation:

The easiest way (at least for me) it is "to see" its value using the unit circle and the meaning of #cos# in terms of the "length"of it.
Consider a circle of radius #1# and on this circle a point #P#. The point produces a projection, depending upon the angle #alpha#, on the horizontal axis that is our #cos# (segment #OA#):
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