Geometry

Question Analysis

The question asks which trigonometric value is positive in Quadrant IV, focusing on the sign conventions of trig functions across quadrants.

Key Concept Explanation

Using the ASTC rule for sign patterns:

Quadrant I: All (+)

Quadrant II: Sin (+)

Quadrant III: Tan (+)

Quadrant IV: Cos (+)

Memory aid: All Students Take Calculus (indicates positive functions per quadrant).

Step-by-Step Solution

1. Recall the coordinates in Quadrant IV:

x > 0 (positive), y < 0 (negative), and r > 0 always.

2. Relate to trig functions:

Sin = (negative, since y < 0).

Cos =

Click "Show Answer" to reveal the answer and analysis