SOLUTION: The solutions of cos 2x = 0, in the interval 0 < x < 360

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Question 303127: The solutions of cos 2x = 0, in the interval 0 < x < 360
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
The solutions of cos 2x = 0, in the interval 0 < x < 360
.
If we
Let y=2x
then we can rewrite
cos 2x = 0
as
cos y = 0
.
From the "unit circle" we know that this will be true when
y = 90 deg and 270 deg
.
Now to find 'x':
y=2x
set y=90
90=2x
45 deg = x
.
set y=270
270=2x
135=x
.
solution: 90 deg and 135 deg