The exact value of cos 60° is:
A$\sqrt{3}/2$ (which is sin 60° instead)
B$1/2$ (which is the correct value)
C$1$ (which is cos 0°)
D$\sqrt{2}/2$ (which is cos 45°)
Answer & Solution
Correct answer: B. $1/2$ (which is the correct value)
cos 60° = 1/2. sin 60° = √3/2. Special angles to memorise: cos goes 1, √3/2, √2/2, 1/2, 0 for 0°, 30°, 45°, 60°, 90°.
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