Hi, I have a problem that says to solve this equation for the interval 0<theta<2 pie which is one revolution of the unit circle. The equation is:(adsbygoogle = window.adsbygoogle || []).push({});

(square root of 2)(cos 2theta) = 1

The cos2theta is a double angle, but I couldn't find any solutions for theta that would = 1 at the end. The answer has to fit in for the theta angle. Is this possibly no solution? I had originally put pie/4 as an answer but realized I forgot the parenthesis in the calculator and now I need to redo the problem. Thanks!

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# Homework Help: Trig Solve for Solution Within Interval

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