Question

How do you find the exact value of $\cos \dfrac{\pi }{3}$ ?

Answer 1

Hint: In this question we have been asked to find the exact value of $\cos \dfrac{\pi }{3}$ . For doing that we will use the concept that we have learnt during the basics of trigonometric that is the trigonometric values table specified for some specific angles.

Complete step by step solution:
Now considering from the question we have been asked to find the exact value of $\cos \dfrac{\pi }{3}$ . For doing that we will use the concept that we have learnt during the basics of trigonometric that is the trigonometric values table specified for some specific angles.
From that table we know that the value of $\cos \dfrac{\pi }{3}$ is mathematically given as $\dfrac{1}{2}$ .
This value can be further simplified and expressed as a decimal by multiplying both the numerator and denominator by 5. After performing this basic arithmetic simplification we will have $\dfrac{1\times 5}{2\times 5}=\dfrac{5}{10}=0.5$ .
Therefore we can conclude that the exact value of $\cos \dfrac{\pi }{3}$ can be given as 0.5 or $\dfrac{1}{2}$ .

Note: While answering questions of this type we should be sure with the concepts that we are going to apply and the calculations that we are performing in between. This is a very simple and easy question and can be answered in a short span of time. Very few mistakes are possible in questions of this type. For example if we do not remember the table specifying trigonometric values and got confused and written the answer as $\dfrac{\sqrt{3}}{2}$ which is a wrong answer. Similarly the value of $\sin \dfrac{\pi }{6}$ is given as 0.5 or $\dfrac{1}{2}$ .