The value of $\cos \,\,9^\circ - \sin \,\,9^\circ $ is

JEE MATHEMATICS MCQ: MULTIPLE AND SUBMULTIPLE ANGLES

1 Easy

1 of 1

Application +4 | -1

The value of

\cos \,\,9^\circ - \sin \,\,9^\circ

View answer and explanation

Correct option: B

\frac{{\sqrt {5 - \sqrt 5 } }}{2}

Option B (

\frac{{\sqrt {5 - \sqrt 5 } }}{2}

) is correct because it is derived from simplifying the expression

\sqrt{1 - \sin 18^\circ}

using the known value of

\sin 18^\circ

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