Edexcel-WJEC-CCEA A Level

Proof
3 Topics
Proof by Exhaustion and Deduction
Example to Try on Proof by Exhaustion and Deduction
Proof by using a Counter-Example
The Factor Theorem
2 Topics
The Factor Theorem
How to solve a cubic equation using the factor theorem
Understand and use graphs of functions
20 Topics
Sketching Quadratic Graphs
Sketching Quadratic Graphs by Completing the Square (part 1)
Sketching Quadratic Graphs by Completing the Square (part 2)
How to Sketch Cubic Graphs
Sketching Reciprocal graphs of the form y=k/x
Sketching graphs of the form k/x^2
How to draw y=|f(x)| graphs
How to draw y=f(|x|) graphs
Exponential Functions
Natural Log, lnx : properties and graph
Trigonometry : Graphs of sec, cosec and cot
Combining functions
Inverse functions : Introduction
Inverse functions : Example 1
Inverse functions : Example 2
Inverse functions : Example 3
Inverse functions – Graphical relationship
More Graphs of common functions
Transformations Playlist
Trigonometric Graphs and Transformations Playlist
Use intersection points of graphs to solve equations
Transformations of curves
2 Topics
Graph Transformations Playlist
Trigonometric Graphs and Transformations Playlist
Use of functions in modelling
4 Topics
Modelling Curves using logarithms
Modelling Curves y=ab^x : Converting to Linear Form (Example)
Modelling Curves y=ax^b : Converting to Linear Form Example
Trigonometric Problem
The coordinate geometry of the circle
7 Topics
Circle Properties You Should Know
Equation of a circle : ExamSolutions
Equation of a Circle (Alternative form)
Finding the Centre and Radius of Circle
Equation of a Circle passing through 3 points
Equation of a Tangent to a Circle
Parametric Equations for a Circle (Example)
Arithmetic sequences and series
7 Topics
Arithmetic Sequences and nth term | Introduction |
Arithmetic Progressions – What are they?
How to Prove the Sum of an Arithmetic Progression
Arithmetic Progressions – Finding a and d given two terms
Arithmetic Progression – Working with consecutive terms
Arithmetic Series Beastie
Arithmetic Sequences and Series – Exam Questions
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Example to Try on Proof by Exhaustion and Deduction

Edexcel-WJEC-CCEA A Level Proof Example to Try on Proof by Exhaustion and Deduction

This is a follow up to an earlier video tutorial where we showed you how to do proof by exhaustion and proof by deduction. In this example you are asked to prove that all cube numbers are a multiple of 9 or 1 more or 1 less than a multiple of 9.