Geometric mean of \(\tan 1^{\circ}, \tan 2^{\circ}, \ldots \ldots . . .\), \(\tan 89^{\circ}\) is

Geometric mean of \(\tan 1^{\circ}, \tan 2^{\circ}, \ldots \ldots . . .\), \(\tan 89^{\circ}\) is
  1. \(\frac{1}{89}\)
  2. 1
  3. \(\frac{1}{3}\)
  4. \(\sqrt{3}\)

Solution

\(\tan 1^{\circ} \cdot \tan 2^{\circ} \ldots \tan 45^{\circ} \cdot \tan 46^{\circ} \ldots \tan 88^{\circ} \cdot \tan 89^{\circ}\) \(\tan 1^{\circ} \cdot \tan 2^{\circ} \ldots \tan 44^{\circ} \cdot \tan 45^{\circ} \tan \left(90-44^{\circ}\right)\) \(\ldots \tan \left(90^{\circ}-1^{\circ}\right)\) \(\tan 1^{\circ} \cdot \tan 2^{\circ} \ldots \tan 44^{\circ} \tan 45^{\circ} \operatorname{Cot} 44^{\circ} \cdot \operatorname{Cot} 43^{\circ}\)... \(\operatorname{Cot} 1^{\circ}\) \(\tan 1^{\circ} \cdot \tan 2^{\circ} \ldots \tan 44^{\circ} 1 \frac{1}{\tan 44^{\circ}} \frac{1}{\tan 43^{\circ}} \cdots \frac{1}{\tan 1^{\circ}}=1\) Hence, option (b) is correct.

Asked in: AP EAMCET 2020 (18 Sep Shift 2)

Practice more Sequences and Series questions on Aicharya