Trigonometric Identities Question 118

Question: $ \tan 1{}^\circ \tan 2{}^\circ \tan 3{}^\circ \tan 4{}^\circ ……..\tan 89{}^\circ = $

[MP PET 1998, 2001; AMU 1999; Pb. CET 1994]

Options:

A) 1

B) 0

C) $ \infty $

D) 1/2

Show Answer

Answer:

Correct Answer: A

Solution:

$ \tan 1{}^\circ \tan 2{}^\circ ….\tan 89{}^\circ $ $ =(\tan 1{}^\circ \tan 89{}^\circ )(\tan 2{}^\circ \tan 88{}^\circ )…… $ $ =1\times 1\times 1….=1. $