Project ForgeGeneral Aptitude
Quantitative Aptitude
GATE 2018
Hard
For integers a, b and c, what would be the minimum and maximum values respectively of a+b+c if log|a|+log|b|+log|c|=0?
- -3 and 3
- B-1 and 1
- C-1 and 3
- D1 and 3
Explanation
log|a|+log|b|+log|c|=0 means log(|a|*|b|*|c|)=0, so |a|*|b|*|c|=1. Since a,b,c are integers, |a|,|b|,|c| are non-negative integers whose product is 1 — the only way is |a|=|b|=|c|=1. So each of a,b,c is -1 or 1. The sum a+b+c ranges from -3 (all -1) to 3 (all 1).
Source: GATE ME 2018 Session 1 (Set 1) (2018)
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