Lesson Notes By Weeks and Term v4 - SHS 2
APPLICATION OF ALGEBRA
Download the Lessonotes Mobile Ghana app for faster lesson access on Android and iPhone.
APPLICATION OF ALGEBRA
Download the Lessonotes Mobile Ghana app for faster lesson access on Android and iPhone.
Subject: Additional Mathematics
Class: SHS 2
Term: 1st Term
Week: 15
Grade code: 2.1.1.LI.10
Strand code: 1
Sub-strand code: 1
Content standard code: 2.1.1.CS.3
Indicator code: 2.1.1.LI.10
Theme: MODELLING WITH ALGEBRA
Subtheme: APPLICATION OF ALGEBRA
This page supports the lesson note with a companion video and a short classroom-ready summary.
For class groups and homework, share this lesson page so learners also get the summary, objectives, and full lesson context.
This lesson revisits and deepens our understanding of rational functions. A rational function is essentially a fraction where the numerator and denominator are polynomials. These functions appear everywhere in real life, from calculating the average cost of producing items in a small business in Madina Market to determining the concentration of a solution in a science lab at PRESEC. By understanding their properties—like where they are defined and where they equal zero—we gain powerful tools for solving practical problems in science, engineering, and economics. This lesson will equip you with the foundational skills to analyse these important functions.
2.1 What is a Rational Function?
A rational function is any function that can be written as a ratio (or fraction) of two polynomial functions. It has the form: `f(x) = P(x) / Q(x)` where `P(x)` and `Q(x)` are polynomials, and importantly, `Q(x) ≠ 0`. `P(x)` is the numerator. `Q(x)` is the denominator.
Simple Analogy: Think of sharing a large bowl of fufu among a group of people. If `P(x)` represents the fufu and `Q(x)` represents the number of people, it makes sense that you can't share it among zero people. The entire concept becomes "undefined." This is the most important rule for rational functions.
2.2 Finding the Domain and Undefined Points