If tan 7θ tan 2θ = 1, then the value of tan

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If tan 7θ tan 2θ = 1, then the value of tan 3θ is

1. √3
2. - 1
  √3
3. 1
  √3
4. - √3

Correct Option: C

tan 7θ . tan 2θ = 1

⇒ tan 7θ =	1	= cot 2θ
	tan 2θ

⇒ tan 7θ = tan (90° – 2θ)
⇒ 7θ = 90° – 2θ
⇒ 9θ = 90° ⇒ θ = 10°

∴ tan 3θ = tan 30° =	1
	√3