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tan 2x + sec 2x = cos x + sin x where 0<=x<=360

I solve it in this way but cannot find the right answer:

(sin 2x + 1) / cos 2x = cos x + sin x

(cos x + sin x)^2 / cos 2x = cos x + sin x

(cos x + sin x) / cos 2x = 1

sqrt(2) cos(x - 45) sec 2x = 1

sec 2x cos(x - 45) = 1 / sqrt(2)

x = 90 or 360

But the correct answers are x = 0 or 270 or 360.

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# Homework Help: Trigonometric equation

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