Mathematical Studies Standard Level for the IB Diploma Scheme of work – Topic 6: Mathematical models Coursebook chapters 17–19 Introduction This scheme of work offers an example route through the specification with suggestions of activities and discussion points that you could consider along the way. For each chapter there are references to the associated PowerPoint file and interactive GeoGebra files, as well as to relevant websites and video clips. The PowerPoint files contain a number of discussion slides that raise Theory of Knowledge questions; students should be encouraged to talk about these both in maths lessons and during specific Theory of Knowledge lessons. The scheme of work, while not intended to cover the syllabus in full, does aim to provide a framework that you can supplement and adapt with your own activities and ideas. Note: Italic text describes suggested uses of the materials referenced. The GeoGebra files referenced in this scheme were created using GeoGebra version 4.2.31.0. Some functions, such as check-boxes, were introduced in this version; so if you have an older version of the software, you will need to download the latest version from the GeoGebra website to be able to use these resources to their full potential. Key [ppt] [tt] [ggb] [V] [www] [TOK] [GDC] PowerPoint activity textbook exercise GeoGebra activity video link useful website Cambridge University Press has no responsibility for the persistence or accuracy of URLs for external or third-party internet websites referred to in this publication, and does not guarantee that any content on such websites is, or will remain, accurate or appropriate. Theory of Knowledge activity GDC question and worked answer Copyright Cambridge University Press 2014. All rights reserved. Page 1 of 8 Mathematical Studies Standard Level for the IB Diploma Topic 6: Mathematical models 20 hours Aims: To understand and identify the characteristics of some common functions and be able to confidently analyse them, sketch their graphs and solve problems using them To learn how to use a function to model a situation and analyse the function to make predictions about the situation Phase Chapter 17: Functions and graphs Estimated time allocation 5 hours Focus from the text What is a function? Learning objectives Activities Links Understand the meaning of a function given in different forms and what the domain and range are for a function [ppt] [TOK] Chapter 17 slides 2–3: Mathematics in nature This activity could be used in a number of places in the course but, since it raises the question of whether maths governs reality or the other way around, it fits particularly well with this topic on mathematical models. Images showing random events as well as more regular patterns and structures are used to generate discussion – no definite answers here but should stimulate some interesting discussions. [www] http://www.mathsisfun.com/sets /function.html [tt] Page 495 Exercise 17.1 ‘Determining the validity of a function’ Functions in more detail Be able to find values relating to functions; be able to determine the domain and range of a function Copyright Cambridge University Press 2014. All rights reserved. [tt] Page 498 Exercise 17.2 ‘Evaluating functions for different values of x’ [www] http://functions.wolfram.com/ The Wolfram functions site [tt] Page 503 Exercise 17.3 ‘Finding the domain and range of a function’ [www] http://www.khanacademy.org [ggb] ch17 domain and range This interactive file allows you to set a function which is either linear or quadratic and then determine the domain and range for the function. Use the check-boxes to choose [www] http://www.mathsisfun.com/sets Page 2 of 8 /math/algebra/algebra-functions /domain-range-codomain.html Page explaining domain and range Mathematical Studies Standard Level for the IB Diploma the type of domain: left, right or between; then either one or two blue points will appear on the curve, and you can move them along the curve to see the corresponding domain and range. The domain will be shown as a red (left), blue (between) or green (right) line segment on the x-axis; the range will be shown as a violet line segment on the y-axis. You can toggle the domain and range on and off independently. Rational functions Drawing graphs and diagrams Understand the nature of rational functions and be able to find the vertical asymptote of such functions Understand the difference between a sketch, a plot and a drawing; be able to sketch, plot and draw graphs [tt] Page 508 Exercise 17.4 ‘Finding asymptotes of rational functions’ /Asymptote.html Page explaining asymptotes [ggb] ch17 rational This interactive file shows the general equation of a simple rational function as defined in the chapter. Each coefficient can be changed using a slider to explore its effect on the graph. This would be suitable for use as a short discovery activity, where students could be asked to explore and deduce the effect on the graph of changing each of the numbers a, b and c. [GDC] Function [ppt] Chapter 17 slides 7–8: Key points of a function This summarises the important features that students need to label on their sketches and can be used to remind students whenever they need to sketch graphs. [tt] Page 512 Exercise 17.5 ‘Drawing or sketching graphs and using them to determine domains and ranges’ [tt] Page 516 Exercise 17.6 ‘Finding values for functions and using their graphs to solve equations’ [ppt] [TOK] Chapter 17 slides 4–6: Do graphs have meaning in themselves? Copyright Cambridge University Press 2014. All rights reserved. [www] http://mathworld.wolfram.com Page 3 of 8 Mathematical Studies Standard Level for the IB Diploma This activity asks students to suggest context for a graph without any markings or labels. What could it be about? The ‘Show’ button reveals the scale and the quantities measured along the axes, but it raises an interesting question about mathematics in real context as opposed to pure maths. Review of Chapter 16 1 hour Geometry of threedimensional solids Secure the skills of solving problems involving 3D shapes by undertaking past paper-style questions Copyright Cambridge University Press 2014. All rights reserved. [tt] Page 488 Mixed examination practice Page 4 of 8 Mathematical Studies Standard Level for the IB Diploma Phase Chapter 18: Linear and quadratic models Estimated time allocation 5 hours Focus from the text Linear models Quadratic functions and their graphs Learning objectives Activities Understand the nature of linear functions and be able to use them to analyse situations modelled by a linear function [tt] Page 526 Exercise 18.1 ‘Using and understanding linear models’ Know the properties of a quadratic function and its graph; be able to find characteristics of a quadratic function from either the graph or the equation Links [ggb] ch18 linear In this simple interactive file, you can use sliders to change the values of the gradient and y-intercept to see how this affects the equation in both forms. It is the reverse version of the GeoGebra file ‘ch14 equation of a line’ in that it allows you to control the parameters directly. It might be useful to highlight this difference by showing both files side by side. [ppt] [TOK] Chapter 18 slides 2–3: The nature of curves This provides a visual stimulus to discuss the difference between straight lines and curves. In addition, it challenges students to think about what makes a curve curved. This links to rates of change in Topic 20 and can be used again at that point. [ggb] ch18 quadratic This is a straightforward interactive file which allows you to manipulate the coefficients of the quadratic function and see what effect this has on the graph’s position and shape. Like many of these GeoGebra files, it has been designed to be used primarily as a student discovery tool; thus you could set up a structured investigative task for students to explore the effect of each coefficient. Equally, though, you could use this activity to summarise the effects for the class. [ggb] ch18 maxima and minima Like ‘ch18 quadratic’, this file allows the coefficients of Copyright Cambridge University Press 2014. All rights reserved. Page 5 of 8 [www] http://www.mathsisfun.com /quadratic-equation-solver.html [www] http://www.mathsisfun.com /algebra/functions-maxima-minima.html Mathematical Studies Standard Level for the IB Diploma the quadratic function to be changed, but in addition to drawing the graph it identifies the associated maximum or minimum point. It can be used to demonstrate how negative values of ‘a’ (the coefficient of x2) give maximum points while positive values give minimum points; but students could also investigate how changing ‘b’ or ‘c’ affects the position of the maximum or minimum point. One question for students to explore would be to relate the values of a, b and c to the coordinates of the turning point. [ggb] ch18 symmetry This is an adaptation of ‘ch18 quadratic’ that displays the equation of the line of symmetry. The line of symmetry is shown as a red line, which remains visible as you adjust the coefficients of the quadratic function using the sliders. [tt] Page 532 Exercise 18.2A ‘Understanding quadratic functions and their characteristics’ Quadratic models Be able to use quadratic models to solve problems in context and make predictions [tt] Page 535 Exercise 18.2B ‘Finding intercepts of quadratic functions’ [ppt] Chapter 18 slides 4–5: Quadratic functions This summarises the key features of quadratic functions and would provide a useful way of reminding students of previous learning prior to its application. [tt] Page 540 Exercise 18.3 ‘Using and understanding quadratic models’ Review of Chapter 17 1 hour Functions and graphs Secure the skills of using functions and their graphs by undertaking past paper-style questions Copyright Cambridge University Press 2014. All rights reserved. [tt] Page 519 Mixed examination practice Page 6 of 8 Mathematical Studies Standard Level for the IB Diploma Phase Chapter 19: Exponential and polynomial functions Estimated time allocation 6 hours Focus from the text Exponential functions and their graphs Learning objectives Activities Links Understand the nature and general form of exponential functions; be able to identify the horizontal asymptote from the equation or by using your GDC [ppt] Chapter 19 slides 2–3: Exponential functions This summarises the properties of exponential functions with reference to the graph, highlighting the y-intercept, horizontal asymptote and growth of the curve. Also shown is the effect of a negative power on the graph. This summary can be used after students have explored and identified these key features using the interactive GeoGebra file. [V] http://youtu.be/Pt2gqODYuAU 14-minute video on exponential functions [ggb] ch19 exponential This interactive file allows students to vary the coefficients of an exponential function and observe the changes to the graph of the function. The horizontal asymptote is shown, and there is a check-box which can be used to switch the function and graph to the negative-power version. Exponential models Polynomial functions Be able to use exponential models to analyse situations and make predictions Understand how quadratic functions can be extended to higher-power functions; understand the concepts of maxima, minima and turning points in relation to Copyright Cambridge University Press 2014. All rights reserved. [tt] Page 551 Exercise 19.1 ‘Finding values and key features of exponential functions’ [tt] Page 556 Exercise 19.2 ‘Using and understanding exponential models’ [GDC] Population growth [ppt] Chapter 19 slides 4–5: Polynomial functions This shows a sequence of simplified images of higherpower polynomial graphs, to prompt students to reflect on the impact the power has on the shape of the curve. Although there are obviously many variations of curve shape, this activity intentionally focuses on helping students appreciate that the number of turns in the curve is, at most, one less than the power. Page 7 of 8 [www] http://www.mathsisfun.com /algebra/polynomials.html Mathematical Studies Standard Level for the IB Diploma the graphs of polynomials Review of Chapter 18 1 hour Modelling with polynomial functions Be able to use your GDC to analyse polynomial models and make predictions Linear and quadratic models Secure the skills of using linear and quadratic functions to solve problems by undertaking past paper-style questions Copyright Cambridge University Press 2014. All rights reserved. [tt] Page 561 Exercises 19.3 ‘Finding the key features of polynomial functions’ [GDC] Multiple functions [tt] Page 564 Exercise 19.4 ‘Using and understanding polynomial models’ [tt] Page 543 Mixed examination practice Page 8 of 8 [www] http://www.mathsisfun.com /algebra/mathematical-models.html