Your formula  is

B29*(B31-G34)^2/2 =0

This would be calculated in this order

B31-G34
^2
/2
*B29
=0

If that is what you meant

Then for the equation to = 0, B31 and G34 must be equal. It does not matter
what B29 is.

If you meant something else, let us know what you did mean, including the
order of calculation.

To resolve the formula  you've given us, either B29 needs to be zero, or B31
and G34 need to contain the same value. A loop  is not needed.