What is the greatest common factor of 15a^3b, 40a^2b^2 and 45ab^3?

Question

anonymous · Answer

$$72a^3 b^3 $$

anonymous · Answer

it says that is not correct

anonymous · Answer

5ab

anonymous · Answer

I am working in a mathlab online and it said that was incorrect....sry robtobey

anonymous · Answer

thank you very much.....can you show me how you got that answer because I would like to learn how to do that please

anonymous · Answer

First look at the numerical coefficients factored.
(5 3) (2 2 2 5) (3 3 3 5)
The only factor element common to all three is 5.

anonymous · Answer

Next deal with the a an b values, a^3*b, a^2*b^2, a b^3
{a a a b, a a b b, a b b b}
The only common factor elements is a and b.
Do you see any errors here?

anonymous · Answer

no

anonymous · Answer

I use Mathematica 8 to do most calculations.  If the input is correct, the output is as good as gold.  The program a zillion functions.  Perhaps you may have used an incorrect MathLab function for the purpose of dealing with this problem.

Back to the problem at hand.  Does 5ab seem to fint the bill?