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Question
State whether the following is true or false. Justify your answer.
sinθ = cosθ for all values of θ.
Options
True
False
Solution
This statement is False.
Explanation:
sin θ = cos θ for all values of θ.
This is true when θ = 45°
As
`sin 45° = 1/sqrt2`
`cos 45° = 1/sqrt2`
It is not true for all other values of θ.
As sin 30° = `1/2` and cos 30° = `sqrt3/2`
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