Inequalities
Inequalities Overview
- Inequalities are mathematical statements used to compare expressions and include symbols like ‘<’, ‘>’, ‘≤’, and ‘≥’.
- Unlike equations, inequalities define a range of solutions rather than a specific solution.
Solving Inequalities
- Solving inequalities is like solving equations, with the goal to isolate the variable.
- Use the BIDMAS order to undertake operations while solving the inequality.
- For instance, to solve the inequality 3x > 12, divide both sides by 3 to get x > 4, means that all values of x greater than 4 satisfy the inequality.
- Important to remember, when an inequality is multiplied or divided by a negative number, the inequality sign must be reversed.
Graphical Representation of Inequalities
- Inequalities can be represented graphically.
- A dashed line indicates a “less than” (<) or a “greater than” (>) inequality, meaning points on the line are not part of the solution.
- A solid line is used for “less than or equal to” (≤) or “greater than or equal to” (≥) inequalities, meaning points on the line are included in the solution.
- Shading is used to illustrate the solution set for the inequality.
- For instance, region above the line is shaded when the y-value is greater than the x-value, and vice versa.
Compound Inequalities
- Compound inequalities are two or more inequalities joined together by “and” or “or”.
- When “and” is used, the solution of the inequality is where the solution sets of the two inequalities overlap.
- When “or” is used, the solution set includes any solutions of either inequality.
Revision and Practice
- Ensure you check your solutions by substitifying values into the original inequality to ensure it holds true.
- Consistent practice in solving and graphing inequalities improves comprehension and proficiency. Apply different inequality problems to hone these skills.
Remember, inequalities provide a versatile tool for solving a variety of algebraic problems and understanding how different quantities relate and contrast to one another.