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Does there exist a function in Mathematica that simply takes out a common factor from a vector/list of expressions? This seems like such a simple operation that I am surprised that I could not find it in Google or the Mathematica help. It could return the common factor and the list without it:

Function[{a b c , b c, c d}] = {c,{a b, b, d}}

Or it could even simply return the common factor:

Function[{a b c , b c, c d}] = c

edit: sorry I was not completely clear. It would factor out algebraic expression too. So:

Function[{x^2 y, x}]

would yield:

{x,{x y, 1}}
share|improve this question
A "common factor", where all having it is a given? Intersection @@ list – ciao Mar 22 '14 at 0:49
up vote 4 down vote accepted
test = {x^2 y, x};

p = PolynomialGCD @@ test
{p, test/p}

test = {a b c e, b c e, c d e, e c};

p = PolynomialGCD @@ test
{p, test/p}


{x, {x y, 1}}
{c e, {a b, b, d, 1}}

share|improve this answer
Thank you! PolynomialGCD was that function! – user2686410 Mar 22 '14 at 1:01

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