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The Value of Cos 1 ∘ Cos 2 ∘ Cos 3 ∘ . . . Cos 179 ∘ is

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Question

The value of \[\cos1^\circ \cos2^\circ \cos3^\circ . . . \cos179^\circ\] is

 

Options

  • \[\frac{1}{\sqrt{2}}\]

     

  • 0

  • 1

  • -1

MCQ
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Solution

\[\cos1^\circ \cos2^\circ \cos3^\circ . . . \cos179^\circ\]
\[ = \cos1^\circ \cos2^\circ \cos3^\circ . . . \cos90^\circ . . . \cos179^\circ\]
\[ = 0 \left( \cos90^\circ = 0 \right)\]

Hence, the correct answer is option 0.

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Chapter 5: Trigonometric Functions - Exercise 5.5 [Page 43]

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RD Sharma Mathematics [English] Class 11
Chapter 5 Trigonometric Functions
Exercise 5.5 | Q 26 | Page 43

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