Question
Solve for $x : \cos \left(\frac{x}{2}+10^{\circ}\right)=\frac{\sqrt{3}}{2}$
✓
Answer
$\cos \left(\frac{x}{2}+10^{\circ}\right)=\frac{\sqrt{3}}{2} $
$ \cos \left(\frac{x}{2}+10^{\circ}\right)=\cos 30 $
$ \frac{x}{2}+10^{\circ}=30^{\circ} $
$x=40^{\circ}$
$ \cos \left(\frac{x}{2}+10^{\circ}\right)=\cos 30 $
$ \frac{x}{2}+10^{\circ}=30^{\circ} $
$x=40^{\circ}$
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