Umm... the parenthesis are irrelevant when it is all multiplication and division (and the division is done after the multiplication from left to right). F = (G * M1 * M2) / r^2 is the same as F = G * M1 * M2 / r^2
Though if you want to get technical, it is usually written as:
code:
M1 * M2
F = G ---------
r^2

[ October 27, 2003, 23:24: Message edited by: Imperator Fyron ]