Question 8 (Multiple Choice Worth 1 point)
(05.02 MC)

If the [tex]\cos 30^{\circ} = \frac{\sqrt{3}}{2}[/tex], then the [tex]\sin 60^{\circ}[/tex] is:

A. 0, because the angles are complementary

B. [tex]\frac{1}{2}[/tex], because the angles are complementary



Answer :

To solve for [tex]\(\sin 60^\circ\)[/tex] given that [tex]\(\cos 30^\circ = \frac{\sqrt{3}}{2}\)[/tex], we can use the fact that the angles are complementary. Complementary angles are two angles that add up to 90 degrees. In trigonometry, the sine of one angle in a right triangle is equal to the cosine of its complementary angle. Hence,

[tex]\[ \sin (90^\circ - \theta) = \cos \theta \][/tex]

For [tex]\(\theta = 30^\circ\)[/tex]:

[tex]\[ \sin 60^\circ = \sin (90^\circ - 30^\circ) = \cos 30^\circ \][/tex]

We are given that:

[tex]\[ \cos 30^\circ = \frac{\sqrt{3}}{2} \][/tex]

Therefore:

[tex]\[ \sin 60^\circ = \frac{\sqrt{3}}{2} \][/tex]

Converting [tex]\(\frac{\sqrt{3}}{2}\)[/tex] to its decimal form, we get approximately 0.8660254037844386. So, the correct answer is:

[tex]\(\sin 60^\circ = \frac{\sqrt{3}}{2}\)[/tex].