Question

cos(2x-pi/4)=sqrt2/2

Answer 1

substitute 2x-pi/4 for "u" and solve it like that first and then plug it back in to that answer

Answer 2

\[\Large \cos(2x-\frac{\pi}{4})=\frac{\sqrt{2}}{2}\] correct?

Answer 3

\[
\Large 2x-\frac{\pi}{4}=\pm \frac \pi 4 + 2 k \pi\\

\]

Answer 4

You can finish it now.