ok i have been given a number of trig problems, and i have not taken trig for about 2 years, now i can remeber how to do the problems, but for the life of me i can't remeber how to get the answer...(adsbygoogle = window.adsbygoogle || []).push({});

ok here is the problem:

sin 2x + cos x = 0; 0<x<2 pi

here is what i got

sin 2x + cos x = 0

2 sin x cos x + cos x = 0

cos x = 0 2 sin x + 1 = 0

sin x = -1/2

here is my problem...

can some one explain to me how do i go from cos x = 0 to x = pi/2

at one point i knew this i just don't remeber... grr so frustrating...

thanks in advance

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# Really easy question

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