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Question
State whether the following is true or false. Justify your answer.
The value of cos θ increases as θ increases.
Options
True
False
Solution
This statement is False.
Explanation:
cos 0° = 1
`cos 30° = sqrt3/2 = 0.866`
`cos 45° = 1/sqrt2 = 0.707`
`cos 60° = 1/2 = 0.5`
cos 90° = 0
It can be observed that the value of cos θ does not increase in the interval of 0° < θ < 90°.
Hence, the given statement is false.
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