cosx(2sinx+1) = 0 ...it looks so easy.(adsbygoogle = window.adsbygoogle || []).push({});

method 1:

distribute: 2sinxcosx + cosx = 0

double angle: sin2x + cosx = 0

sin2x = -cosx

here I'm getting stuck.

Method 2:

I try to use the zero product property

cosx = 0

2sinx + 1 = 0

x = pi/2 + 2pi(k) , 3pi/2 + 2pi(k)

x = pi/6 + 2pi(k) , 5pi/6 + 2pi(k)

Where am I going wrong?

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# Homework Help: Solving for x (Trig)

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