Trigonometryhard · Past Paper
If sin θ - cos θ = 0, find the value of sin⁴θ + cos⁴θ.
A1
B3/4
C1/2
D1/4
✓ Correct Answer: C — 1/2
sin=cos implies θ=45. sin⁴45 + cos⁴45 = (1/√2)⁴ + (1/√2)⁴ = 1/4 + 1/4 = 1/2.
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