Inequalities
Overview
Equations tell you exactly where two expressions are equal, but in mathematics and real life you often need to know where one quantity is larger or smaller than another. Inequalities give you a way to describe entire ranges of values, not just single solutions, and they appear throughout the 4PM1 specification whenever a question asks for a set of values rather than a point.
You will learn to solve linear and quadratic inequalities algebraically, represent linear inequalities in two variables on a coordinate grid, and tackle introductory linear programming problems. Every technique builds on algebra you already know, with a few critical sign rules that catch out even confident students.
Objectives
- Solve simple linear and quadratic inequalities
- Represent linear inequalities in two variables graphically
- Solve simple problems on linear programming
Mind map
This topic is mapped out so you can see how the ideas connect.
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Flashcards
Quick recall practice on the facts this topic is tested on.
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Lesson Note
Complete Note Available on the Green Bridge App
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Lesson Evaluation
Congratulations on completing the lesson on Inequalities. Now that youve explored the key concepts and ideas, its time to put your knowledge to the test. This section offers a variety of practice questions designed to reinforce your understanding and help you gauge your grasp of the material.
You will encounter a mix of question types, including multiple-choice questions, short answer questions, and essay questions. Each question is thoughtfully crafted to assess different aspects of your knowledge and critical thinking skills.
Use this evaluation section as an opportunity to reinforce your understanding of the topic and to identify any areas where you may need additional study. Don't be discouraged by any challenges you encounter; instead, view them as opportunities for growth and improvement.
- Solve 3x - 5 > 7. A) x > 4 B) x > 2 C) x < 4 D) x > 12 Answer: A
- Which values of x satisfy x^2 - 4x - 5 < 0? A) x < -1 or x > 5 B) -1 < x < 5 C) x < -5 or x > 1 D) -5 < x < 1 Answer: B
- When solving an inequality, what must you do if you divide both sides by a negative number? A) Nothing changes B) Reverse the inequality sign C) Square both sides D) Add 1 to both sides Answer: B
- In a linear programming problem, the optimal value of the objective function occurs at: A) The centre of the feasible region B) Any point on a boundary line C) A vertex of the feasible region D) The origin Answer: C
- The boundary line for the inequality 2x + y < 6 should be drawn as: A) A solid line B) A dashed line C) A dotted line with arrows D) A double line Answer: B
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Practice Mock Questions
Want to practice mock questions on Inequalities? Download the Green Bridge CBT app to access mock questions and full practice assessments for this topic.
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