WBJEE · Maths · Trigonometric Ratios & Identities
The value of \(\cos 15^{\circ}-\sin 15^{\circ}\) is
- A 0
- B \(\frac{1}{\sqrt{2}}\)
- C \(-\frac{1}{\sqrt{2}}\)
- D \(\frac{1}{2 \sqrt{2}}\)
Answer & Solution
Correct Answer
(B) \(\frac{1}{\sqrt{2}}\)
Step-by-step Solution
Detailed explanation
Hints : \(\cos 15^{\circ}-\sin 15^{\circ}=\sqrt{2} \cos 60^{\circ}=\frac{1}{\sqrt{2}}\)
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