यदि sin θ = 3/5 हो, तो cos θ का मान होगा:

उत्तर: (C) 4/5 — sin²θ + cos²θ = 1. cos²θ = 1 - (3/5)² = 1 - 9/25 = 16/25. cos θ = 4/5. This uses the Pythagorean identity and the 3-4-5 right triangle.