(1)Use the binomial theorem to find the 18th term in the binomial expansion of [2m-n(sqrt(2)]^27
Usually the letter n is used to represent a general number, not a specific
number, but here n is used as a specific number, so I can't speak of the "nth
term", so I'll have to speak of the "pth" term instead to avoid conflict of
letters.
The pth term of
, if you start counting with 0 instead of 1, is
,
where
is the binomial coefficient which is the same as
C(s,p) or sCp or "the number of combinations of s things taken p at a time."
The 18th term is the 17th term if we start counting from 0, so we
substitute
,
,
,
into
and simplify a little:
Further simplifying the factors separately:
=
<-- using a TI-84 calculator
=
=
=
=
=
=
=
=
=
Putting them all together:
<-- answer
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(2)Find the 69th number in the 72nd row (n=72) of Pascal’s triangle.
Again we start counting from 0, so the 69th number starting counting with 1,
is the 68th number, when we start counting with 0 instead of 1.




If you can't use a calculator you can use








.
<-- answer
Edwin