Extraneous Solution

Definition

An extraneous solution is a solution to an equation that does not satisfy the original constraints or conditions of the problem. It is a solution that is mathematically valid but does not represent a valid answer within the context of the problem being solved.

5 Must Know Facts For Your Next Test

1. Extraneous solutions can arise when solving rational equations due to the restricted domain of the rational expressions involved.
2. The process of solving a rational equation may introduce extraneous restrictions, which can lead to extraneous solutions that do not satisfy the original equation.
3. Extraneous solutions must be identified and discarded to ensure that the final solution set accurately represents the valid solutions to the original rational equation.
4. Checking the solutions by substituting them back into the original equation is a crucial step to identify and eliminate any extraneous solutions.
5. Awareness of the potential for extraneous solutions is important when solving rational equations, as these solutions can lead to incorrect conclusions if not properly recognized and handled.

Review Questions

• Explain how extraneous solutions can arise when solving rational equations.
  • Extraneous solutions can arise when solving rational equations due to the restricted domain of the rational expressions involved. During the process of solving the equation, extraneous restrictions may be introduced, which can lead to solutions that satisfy the transformed equation but do not actually satisfy the original rational equation. This happens because the steps taken to solve the equation, such as cross-multiplying or clearing denominators, can introduce new conditions that are not part of the original problem statement.
• Describe the importance of identifying and discarding extraneous solutions when solving rational equations.
  • Identifying and discarding extraneous solutions is crucial when solving rational equations, as these solutions do not represent valid answers within the context of the original problem. Including extraneous solutions in the final solution set can lead to incorrect conclusions and interpretations. By carefully checking the solutions by substituting them back into the original equation, you can ensure that the final solution set accurately represents the valid solutions to the rational equation, without any extraneous solutions that do not satisfy the original constraints or conditions of the problem.
• Analyze the relationship between the restricted domain of a rational equation and the potential for extraneous solutions.
  • The restricted domain of a rational equation, which is the set of values for the variable that make the denominator of the rational expression equal to zero, is directly related to the potential for extraneous solutions. When solving a rational equation, the process may introduce new conditions or restrictions that are not part of the original problem statement. These extraneous restrictions can lead to solutions that satisfy the transformed equation but do not actually satisfy the original rational equation, resulting in extraneous solutions. Understanding the connection between the restricted domain and the possibility of extraneous solutions is crucial when solving rational equations, as it allows you to carefully analyze the solutions and ensure that only the valid ones are included in the final solution set.

Related terms

Rational Equation: A rational equation is an equation that contains one or more rational expressions, where a rational expression is a quotient of two polynomials.

Restricted Domain: The restricted domain of a rational equation is the set of values for the variable that make the denominator of the rational expression equal to zero, as these values are not valid solutions.

Extraneous Restriction: An extraneous restriction is a condition or constraint that is introduced when solving an equation, but does not actually belong to the original problem statement.