A Level Maths Notes: C2 - Problems involving the Binomial Expansion
Sometimes we have to go just a little bit further than expand a
bracket using the binomial theorem. We may have two brackets
multiplied together, both brackets raised to a power. We may have to
expand the brackets up to the term in
for
example. We do this by expanding each bracket using the binomial
theorem, ignoring higher powers than
then
multiplying the brackets, again ignoring higher powers than![]()
Example: Expand![]()
Nothing needs to be done to the first bracket but the second can
be expanded to give
Now
expand the brackets against each other.
This
last expression simplifies to
hence
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