Tan 15=?

1.	Tan 15=?
Answer» Let tan(15°) = tan(45°-30°) We know that tan(A - B) = (tanA - tanB) /(1 + tan A tan B) ⇒tan(45°-30°) = (tan45°- tan30°)/(1+tan45°tan30°) = {1- (1/√3)} / {1+(1/√3)} ∴ tan15° = (√3 - 1) / (√3 + 1)

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