log |a| + log |b| + log |c| = 0
It is possible only,
when |a|, |b| and |c| all are equal to 1.
∴ a, b, c may be ±1, ±1, ±1 respectively.
Now for minimum value of all thr ee will be negative.
∴ minimum value = - 3
and maximum value of all three will be positive.
∴ maximum value = +3