Trigonometryhard · Past Paper
Evaluate: 5 sin^2 30 + cos^2 45 - 4 tan^2 30
A5/12
B7/12
C1
D0
✓ Correct Answer: A — 5/12
5(1/4) + 1/2 - 4(1/3) = 5/4 + 2/4 - 16/12 = 7/4 - 4/3 = (21-16)/12 = 5/12.
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