What is the exact value of cos 60 degrees?
Answer and explanation
Correct answer: C. 1/2, from the 30-60-90 special triangle
- Step 1: In a 30-60-90 triangle with hypotenuse 2 the side next to 60 degrees is 1. Step 2. cos 60 = adjacent/hypotenuse = 1/2. Answer: 1/2. Why not the others: the other values belong to other angles or to sine.
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