Easy -1.2 This is a straightforward application of the binomial expansion formula for negative indices, requiring only substitution of n=-3 and b=2, then simplifying three coefficients. It's a routine drill exercise with no problem-solving element, making it easier than average but not trivial since students must handle negative indices and fractional arithmetic correctly.
1 Expand $( 1 + 2 x ) ^ { - 3 }$ in ascending powers of $x$, up to and including the term in $x ^ { 2 }$, simplifying the coefficients.
\hfill \mbox{\textit{CAIE P3 2010 Q1 [3]}}