How do you solve $0=1/2cos2x$ between 0 and 2pi?

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Answer 1 · 2016-02-25T17:19:43

$x=pi/4 or 3pi/4 or 5pi/4 or 7pi/4$

$(1/2)cos2x=0$ means

$cos2x=0$ .

But within the domain $[0,2pi]$ , cosine of an angle is zero for $2x=pi/2$ , $2x=3pi/2$ , $2x=5pi/2$ and $2x=7pi/2$ .

Hence $x=pi/4 or 3pi/4 or 5pi/4 or 7pi/4$

How do you solve 0=1/2cos2x 0=1/2cos2x between 0 and 2pi?