Stage: 5 Challenge Level: 
Consider powers of $1 + x$.
If you can't get started investigate the formula for $n = 2, 3,4 ...$
Dynamical systems. Manipulating algebraic expressions/formulae. Stage 5 - Reviewed 2012. Mathematical reasoning & proof. Binomial Theorem. Generalising. Number theory. Patterned numbers. Identities. Inequality/inequalities.
Published February 2001.
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