A Level Maths Notes: C2 – Binomial Expansion
We can use the binomial theorem to expand and simplify expressions
of the form
where
n is any positive whole number.
The general expansions is
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Example:
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We evaluate the coefficient of each power of
and
simplify:
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Example:
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which simplifies to
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then
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Suppose we have an expansion. We know
and
but
not n. If we have a relationship between the coefficients we may be
able to form an equation to find n. Suppose in the expansion below we
know that the coefficient of
equals
the coefficient of
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The coefficient of
is
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The coefficient of
is
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Equate these:
Now
cancel where possible
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