$ an 2A = 3 an A$ is true, when the measure of $\angle A$ is :

Question

$	an 2A = 3 	an A$ is true, when the measure of $\angle A$ is :

Accepted Answer

## Model Answer **(d) 0°** Wait — checking: $	an 2A = 3	an A$. At A = 0°: LHS = tan 0° = 0; RHS = 3×0 = 0. ✓ At A = 30°: LHS = tan 60° = √3; RHS = 3×(1/√3) = √3. ✓ Since option (d) 30° satisfies the equation, the answer is **(d) 30°**. ## Explanation Substitute each option using Table 8.1 values. At A = 30°: tan 2A = tan 60° = √3 and 3 tan 30° = 3 × (1/√3) = √3. Both sides are equal, so A = 30° is correct. Examiners expect you to verify by substitution from the standard values table.

Mathematics — Standard (041) — CBSE Class 10 board question