Trigonometryhard · Past Paper
A ladder rests against a vertical wall at angle α. If its foot is pulled distance 'a' so it makes angle β, the distance 'b' it slides down is:
Aa (cosβ - cosα) / (sinα - sinβ)
Ba (sinα - sinβ) / (cosβ - cosα)
Ca tan(α+β)
DInsufficient data
✓ Correct Answer: B — a (sinα - sinβ) / (cosβ - cosα)
a = L(cos β - cos α), b = L(sin α - sin β). Thus b = a (sin α - sin β) / (cos β - cos α).
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