If the \( \sin 30^{\circ} \) is \( \frac{1}{2} \), then the \( \cos \overbrace{}^{\circ}= \) \( 60^{\circ} ; \frac{1}{2} \) \( 30^{\circ} ; \frac{\sqrt{2}}{2} \) \( 60^{\circ} ; \frac{\sqrt{3}}{2} \) \( 30^{\circ} ; 1 \)

Did you know that the sine and cosine functions are co-functions? This means that the sine of an angle is equal to the cosine of its complementary angle! In this case, since \( \sin 30^{\circ} = \frac{1}{2} \), it follows that \( \cos 60^{\circ} = \frac{1}{2} \) as well! So the correct relationship here is that \( \cos 60^{\circ} = \frac{1}{2} \). When working with angle measures, it's important to remember the unit circle, where sine and cosine derive their values. The positions of key angles like \( 30^{\circ}, 45^{\circ}, \) and \( 60^{\circ} \) have become classic benchmarks. For example, \( \cos 30^{\circ} \) actually equals \( \frac{\sqrt{3}}{2} \). Knowing these values can help you solve a whole range of math problems quickly and efficiently!