Q. 205.0( 4 Votes )

# The value of cos 1° cos 2° cos 3°…… cos 180° is

A. 1

B. 0

C. -1

D. None of these

Answer :

Given,

cos 1° cos 2° cos 3° ………………..cos 180°

cos 1° × cos 2° × cos 3° …… cos 89° × cos 90° × cos 91° ……….cos 180°

As we know from the table,

cos 90° = 0

Therefore,

cos 1° × cos 2° × cos 3° …… cos 89° × 0 × cos 91° ……….cos 180°

= 0

Rate this question :

How useful is this solution?

We strive to provide quality solutions. Please rate us to serve you better.

Related Videos

Quiz | Task on Trigonometric Ratios46 mins

Basic Concepts of Trigonometry45 mins

Quiz on Trigonometric Ratios31 mins

Trigonometric Identities33 mins

Champ Quiz | Trigonometric Identities33 mins

T- Ratios of Specified Angles58 mins

NCERT | Trigonometric Identities52 mins

Trigonometric Identities44 mins

Trick to learn all Trigonometric Formulae28 mins

Testing the T- Ratios of Specified Angles57 mins

Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Expertsview all courses

Dedicated counsellor for each student

24X7 Doubt Resolution

Daily Report Card

Detailed Performance Evaluation

RELATED QUESTIONS :

Prove the following identities :

tan^{4}θ + tan^{2}θ = sec^{4}θ – sec^{2}θ

Prove the followings identities:

KC Sinha - Mathematics

If, sin 50° = α then write the value of cos 50° in terms of α.

KC Sinha - MathematicsProve the following identities :

sin^{2} θ(1+ cot^{2} θ) = 1

Prove the following identities :

cos^{2} A (tan^{2} A+1) = 1

If sin 77° = x, then write the value of cos 77^{o} in terms of x.

Prove the followings identities:

KC Sinha - Mathematics