Stage: 5 Challenge Level: 
Investigate what happens when you put $n=2$ in the expression. Then try $n=3$, $4$ and $5$.
Quadratic equations. Stage 5 - Reviewed 2012. alphas. Long problems. Diophantine equations. Inequality/inequalities. Mathematical reasoning & proof. Pythagoras' theorem. epsilons. Manipulating algebraic expressions/formulae.
Published March 1999.
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