Question

Suppose tanΘ = 3/5, and that Θ is in quadrant I. Find tan2Θ.

Answer 1

15/8

Explanation:

tan 2θ = 2 tan θ / (1 − tan² θ)

tan 2θ = 2 (3/5) / (1 − (3/5)²)

tan 2θ = (6/5) / (1 − 9/25)

tan 2θ = (6/5) / (16/25)

tan 2θ = (6/5) × (25/16)

tan 2θ = 15/8