You're actually asking about their resolving power, not resolution. Wikipedia and Cambridge in Colour both offer good entry level explanations of these subjects.
Also check out DPreview's test results - the ISO12233 resolving power test charts. This will let you compare all three cameras.
But in the end - there's much more to any camera than it's resolving power capabilities so my advice would be not to overestimate it.
|Umbrellas by pleytime|
from An A to Z of Subjects- Week 21, U
|Glass ball on a perforated metal plate _2 by harubux|