Select the correct answer:

Which of the following is a solution to [tex]\sin \frac{x}{2} = \frac{\sqrt{3}}{2}[/tex]?

A. [tex]60^{\circ}[/tex]
B. [tex]150^{\circ}[/tex]
C. [tex]210^{\circ}[/tex]
D. [tex]240^{\circ}[/tex]



Answer :

Consider the trigonometric equation:

[tex]\[ \sin \frac{x}{2} = \frac{\sqrt{3}}{2} \][/tex]

We know from trigonometry that [tex]\(\sin \theta = \frac{\sqrt{3}}{2}\)[/tex] when [tex]\(\theta = 60^\circ\)[/tex] or [tex]\(\theta = 120^\circ\)[/tex].

So, we set:

[tex]\[ \frac{x}{2} = 60^\circ \quad \text{or} \quad \frac{x}{2} = 120^\circ \][/tex]

To find [tex]\(x\)[/tex], we solve each equation:

1. [tex]\(\frac{x}{2} = 60^\circ\)[/tex]
[tex]\[ x = 2 \times 60^\circ = 120^\circ \][/tex]

2. [tex]\(\frac{x}{2} = 120^\circ\)[/tex]
[tex]\[ x = 2 \times 120^\circ = 240^\circ \][/tex]

Thus, the possible solutions for [tex]\(x\)[/tex] are [tex]\(120^\circ\)[/tex] and [tex]\(240^\circ\)[/tex].

Next, we compare these solutions with the given options:
- A. [tex]\(60^\circ\)[/tex]
- B. [tex]\(150^\circ\)[/tex]
- C. [tex]\(210^\circ\)[/tex]
- D. [tex]\(240^\circ\)[/tex]

Among the options provided, [tex]\(240^\circ\)[/tex] matches our solution.

Therefore, the correct answer is:

[tex]\[ \boxed{4} \][/tex]