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Combine and simplify expressions as much as possible.
Solve equations for x.
1 1 1 2 1 1 3 3 1 1 4 6 4 1 1 5 10 10 5 1
...in which elements in a row are the sum of the two elements in the row above it. These numbers are the Binomial Coefficients.
is the cube of the binomial so the coefficients can be taken from the third row above:
1 3 3 1
and the exponents on start with and count down, while the exponents on
start with and count up:
which simplifies to:
as previously.
if a product is zero one of its factors must be zero so:
either or or
and either or or
 DickFurnas  01 Mar 2007