Find all solutions in the interval [0, 2π).

cos x = sin x

Question

Find all solutions in the interval [0, 2π).

cos x = sin x

accessdenied · Answer

I think unit circle would be useful here.  I assume you are familiar with it?

On the unit circle, the points are in the form (cos x, sin x).  We want the points with the same x-value as y-value there.

accessdenied · Answer

The actual angles that we want, we just find the angle from the positive x-axis to the line containing that point and the origin.
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anonymous · Answer

these are the options

anonymous · Answer

@AccessDenied

accessdenied · Answer

Okay, but just so that we know how to find the answer.  :)
Here would be the unit circle, and the points we want lie on the line y = x.  They happen to be (sqrt(2)/2, sqrt(2)/2) and (-sqrt(2)/2, -sqrt(2)/2).
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We simply identify those two angles for our answer.  Does that make sense?