Question 960547
Find all solutions if 
0 &#8804; x < 2&#960;.
Use exact values only. (Enter your answers as a comma-separated list.) 
cos 2x cos x &#8722; sin 2x sin x = square root of 2 over 2 
x=?
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Identity: cos(x+y)=cosxcosy-sinxsiny
cos 2x cos x &#8722; sin 2x sin x = square root of 2 over 2
cos(2x+x)=&#8730;2/2
2x+x=&#960;/4, 7&#960;/4
3x=&#960;/4, 7&#960;/4
x=&#960;/12, 7&#960;/12