Trigonometryhard · Past Paper
Simplify: (cos A + sin A) / (cos A - sin A) - (cos A - sin A) / (cos A + sin A).
A2 tan 2A
B2 cot 2A
Ctan 2A
Dcot 2A
✓ Correct Answer: A — 2 tan 2A
Expression is ((cos+sin)² - (cos-sin)²) / (cos²-sin²) = (4 sin A cos A) / cos 2A = 2 sin 2A / cos 2A = 2 tan 2A.
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