Geometry

Question Analysis

The main focus is to determine which trigonometric function is appropriate when the adjacent side and the hypotenuse of a right - triangle are given. It requires understanding the definitions of sine, cosine, and tangent in relation to the sides of a right - triangle.

Key Concept Explanation

Sine (sin): Defined as , which involves the opposite side, not the adjacent side.

Cosine (cos): Defined as , so it directly uses the adjacent side and the hypotenuse.

Tangent (tan): Defined as , and it does not involve the hypotenuse in this form.

Step - by - Step Solution

1. Analyze sine: Since sine requires the opposite side and we have the adjacent side, sine is not applicable.

2. Analyze cosine: Cosine's formula

Click "Show Answer" to reveal the answer and analysis