Skip to main content
Ch. 3 - Polynomial and Rational Functions
Lial - College Algebra 13th Edition
Lial13th EditionCollege AlgebraISBN: 9780136881063Not the one you use?Change textbook
Chapter 4, Problem 63

Solve each rational inequality. Give the solution set in interval notation. 1 /(x+ 2) > 1 /(x -3)

Verified step by step guidance
1
Start by writing the inequality clearly: \(\frac{1}{x + 2} > \frac{1}{x - 3}\).
Bring all terms to one side to compare to zero: \(\frac{1}{x + 2} - \frac{1}{x - 3} > 0\).
Find a common denominator and combine the fractions: \(\frac{(x - 3) - (x + 2)}{(x + 2)(x - 3)} > 0\).
Simplify the numerator: \(\frac{x - 3 - x - 2}{(x + 2)(x - 3)} = \frac{-5}{(x + 2)(x - 3)} > 0\).
Analyze the inequality \(\frac{-5}{(x + 2)(x - 3)} > 0\) by considering the sign of the denominator and the fact that the numerator is a constant negative number; determine intervals where the entire expression is positive, and exclude values that make the denominator zero (i.e., \(x \neq -2\) and \(x \neq 3\)).

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
9m
Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Rational Inequalities

Rational inequalities involve expressions with variables in the denominator. Solving them requires finding values of the variable that make the inequality true, while ensuring the denominator is never zero to avoid undefined expressions.
Recommended video:
Guided course
3:21
Nonlinear Inequalities

Finding a Common Denominator and Combining Fractions

To compare or combine rational expressions, rewrite them with a common denominator. This allows you to subtract or add the fractions and transform the inequality into a single rational expression, simplifying the problem.
Recommended video:
Guided course
02:58
Rationalizing Denominators

Sign Analysis and Interval Testing

After simplifying the inequality, determine where the expression is positive or negative by identifying critical points (zeros and undefined points). Test intervals between these points to find where the inequality holds, then express the solution in interval notation.
Recommended video:
05:18
Interval Notation