Absolute Value Inequalities

Two Types

Absolute value inequalities come in two forms, each with a different approach.


Type 1: Less Than

∣x∣<3|x| < 3 means xx is less than 3 units from zero.

So xx is between −3-3 and 33.

∣A∣<B|A| < B becomes −B<A<B-B < A < B

This is an “and” situation. Both conditions must be true.


Example


Type 2: Greater Than

∣x∣>3|x| > 3 means xx is more than 3 units from zero.

So x<−3x < -3 or x>3x > 3.

∣A∣>B|A| > B becomes A<−BA < -B or A>BA > B

This is an “or” situation. Either condition works.


Summary

InequalityKeywordSolution
∥A∥<B\|A\| < BBetween−B<A<B-B < A < B
∥A∥>B\|A\| > BOrA<−BA < -B or A>BA > B

Less than → trapped between two values

Greater than → escaped to the outer regions