Nếu tan(a + b) = 3, tan(a – b) = ‒3 thì tan2a bằng: A. 0. B. \(\frac{3}{5}\). C. 1. D. \( - \frac{3}{4}\).

Nếu tan(a + b) = 3, tan(a – b) = ‒3 thì tan2a bằng:

A. 0.

B. \(\frac{3}{5}\).

C. 1.

D. \( - \frac{3}{4}\).