Stage: 4 and 5 Challenge Level: 
What are the ratios of the sides of a 30, 60, 90 degree
triangle?
Isosceles triangles. Index notation/Indices. Golden ratio. Pythagoras' theorem. Cosine rule. Surds. Long problems. Quadratic equations. Stage 5 - Core Mapping. Mathematical reasoning & proof.
Published June 1998.
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