Trigonometrymedium · Past Paper
Express tan 2A in terms of tan A.
A2 tan A / (1 + tan² A)
B2 tan A / (1 - tan² A)
C(1 - tan² A) / 2 tan A
Dtan² A / (1 - tan A)
✓ Correct Answer: B — 2 tan A / (1 - tan² A)
This is the standard double angle formula for tangent.
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