Add, subtract, multiply, and divide rational expressions as a closed system like rational numbers.
State restrictions before simplifying a rational expression
Problem
What restrictions apply before simplifying this rational expression? \((x^2~-~1)/(x~-~1)\)
Big Picture
What this problem is really about
Restrictions belong to the original expression, so determine them before factoring or cancellation. Set each original denominator equal to zero and exclude those solutions; zeros that occur only in numerators are not restrictions. A later cancellation may hide a denominator factor from the simplified formula, but it leaves the corresponding input missing from the domain.
Inside Gozunta
Turn the preview into practice.
More than a preview
Gozunta lets you study this problem—and more than 10,000 others.
Create targeted learning sessions, use hints, check your answer, read the walkthrough, watch the video, print the work, and track your progress.