Question

Evaluate \( \cos 1^\circ \cdot \cos 2^\circ \cdot \cos 3^\circ \cdots \cos 90^\circ \).

• A. \(0\)
• B. \(1\)
• C. \(-1\)
• D. \(\sqrt{2}\)

Hint:

When a product includes any factor equal to \(0\), the whole product is \(0\) — no further computation needed.

Answer 1

The Correct Option is A

Step 1: Note the factor \(\cos 90^\circ\).
We know \(\cos 90^\circ = 0\).
Step 2: Use zero-product property.
Since the product includes the factor \( \cos 90^\circ = 0 \), the entire product equals \(0\).