Find the exact value of .

MATHEMATICS · Single correct · ISC · Mathematics · Sets and Functions · Sets and Functions

Problem

Find the exact value of

\cos 15^\circ

. (a)

\dfrac{\sqrt{6}-\sqrt{2}}{4}

(b)

\dfrac{\sqrt{6}+\sqrt{2}}{4}

(c)

\dfrac{\sqrt{6}}{4}

(d)

\dfrac{\sqrt{3}}{2}