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Question
sin(45° + θ) – cos(45° – θ) is equal to ______.
Options
2cosθ
0
2sinθ
1
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Solution
sin(45° + θ) – cos(45° – θ) is equal to 0.
Explanation:
sin(45° + θ) – cos(45° – θ)
= cos[90° – (45° + θ)] – cos(45° – θ) ...[∵ cos(90° – θ) = sinθ]
= cos(45° – θ) – cos(45° – θ)
= 0
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