Making mathematical expressions as balanced trees as possible I am having some trouble with turning the following mathematical expressions into as balanced binary trees as possible.

This is what I have done so far, but is there a way to make them even more balanced?

$( − 3)(^2 +  − 1)$



$4( − 1)( − 2)( − 3)$
Since these are mathematical expressions, you can bracket the second one as (4 (x-1)) ((y-2) (z-3)) to make it more balanced. In many programming languages this wouldn't be allowed, because with floating point arithmetic, the order of operations will often change the result. 

Can't see any way to improve the first one.