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marasofia1616
Find all solutions in the interval [0, 2π). cos x = sin x
both of these are equal at theta= pi/4
sinx=cosx then tanx=1 hence x=pi/4 and 5pi/4
now find those pi/4 s in 0 to 2 pi
general sol. is n(pi) + pi/4 where n is an integer