Question

\(\cos 60^\circ = \)

• A. \(\frac{1}{2}\)
• B. \(\frac{\sqrt{3}}{2}\)
• C. \(\frac{1}{\sqrt{2}}\)
• D. 1

Hint:

Remember the relationship \(\cos 60^\circ = \sin 30^\circ = 1/2\) and \(\sin 60^\circ = \cos 30^\circ = \sqrt{3}/2\). This pairing of complementary angles can help you memorize the values more easily.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
This question asks for the standard value of the cosine function for the angle 60 degrees.

Step 2: Key Formula or Approach:
This is a fundamental value in trigonometry. We can recall it from memory or use the complementary angle identity \(\cos \theta = \sin(90^\circ - \theta)\).

Step 3: Detailed Explanation:
The value of \(\cos 60^\circ\) is a standard result from the properties of a 30-60-90 triangle.
\[ \cos 60^\circ = \frac{1}{2} \] Alternatively, using the complementary angle identity:
\[ \cos 60^\circ = \sin(90^\circ - 60^\circ) = \sin 30^\circ = \frac{1}{2} \]

Step 4: Final Answer:
The value of \(\cos 60^\circ\) is \(\frac{1}{2}\).