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Question
The value of the expression (sin 80° – cos 80°) is negative.
Options
True
False
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Solution
This statement is False.
Explanation:
We know that,
sin θ increases when 0° ≤ θ ≤ 90°
cos θ decreases when 0° ≤ θ ≤ 90°
And (sin 80° – cos 80°) = (increasing value-decreasing value) which is always equal to a positive value.
∴ (sin 80° – cos 80°) > 0, which is positive ...(Not negative).
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