(i) If x = 30°, verify that tan 2x = 2tanx/ (1- tan2 x).
(ii) If x = 15°, verify that 4 sin 2x cos 4x sin 6x = 1.
Answer :
(i) x = 30°
Consider LHS = tan 2x
Substituting the value of x
= tan 60°
= √3
Hence, LHS = RHS.
(ii) x = 15°
2x = 15 × 2 = 30°
4x = 15 × 4 = 60°
6x = 15 × 6 = 90°
LHS = 4 sin 2x cos 4x sin 6x
= 4 sin 30° cos 60° sin 90°
= 4 × ½ × ½ × 1
= 1
= RHS
Hence, LHS = RHS.
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