Teaching Schedule for Chapter 5 – Logarithmic Functions NF Week Date Time Ratio Section 5.1 Common Logarithms A Definition of Common Logarithms B Properties of Common Logarithms • Understand the definition of common logarithms. • Learn the properties of common logarithms. • Apply the properties of common logarithms to solve problems. 5.2 Logarithmic Equations • Learn how to solve logarithmic equations. • Learn how to solve exponential equations by converting them into logarithmic equations. 5.3 Applications of Logarithms A Sound Intensity Level B Richter Scale C Logarithmic Transformation 3 • Teachers should introduce the definition of common logarithms. • Teachers may use Activity 5.1 to let students explore the properties of common logarithms. • Teachers may derive the properties of common logarithms from the laws of indices. • Teachers should illustrate the applications of the properties of common logarithms with examples. • Teachers should introduce the concept of logarithmic equations. • Demonstrate how to apply the properties of common logarithms to solve exponential and logarithmic equations with examples. Example Activity IT Teaching Classwork Further Practice Exercise Animation / Video: p. 5.4, 5.7 Applications of Logarithms 5-Minute Lecture: Common Logarithms Extra IT Activity: Properties of common logarithms p. 5.6, 5.10 Exercise 5A (p. 5.10) Level 1: 1 – 23 Level 2: 24 – 40 Rev. Ex. 5 (p. 5.46) Level 1: 1, 5, 8, 10 – 11 Level 2: 32 – 33, 35 – 36, 38, 40 5.6 – 5.8 Teaching Examples 5.6 – 5.8 Teaching Examples (Extra) 5.6, 5.7 5-Minute Lecture: Logarithmic Equations p. 5.14 • Appreciate the applications of • Teachers should use various real-life logarithms in real-life situations situations to illustrate the applications of such as measuring sound intensity logarithms. and the magnitude of an earthquake, and logarithmic transformation. 5.9 – 5.12 Teaching Examples 5.9 – 5.12 Teaching Example (Extra) 5.10 5-Minute Lecture: Applications of Logarithms 5.4 Logarithms to an Arbitrary Base A Definition of Logarithms to an Arbitrary Base B Properties of Logarithms to an Arbitrary Base • Understand the definition of logarithms to an arbitrary base. • Learn the properties of logarithms to an arbitrary base. • Apply the properties of logarithms to an arbitrary base to solve problems. 5.13 – 5.15 Teaching Examples 5.13 – 5.15 Teaching Example (Extra) 5.14 5-Minute Lecture: p. 5.23, 5.25 p. 5.27 Logarithms to an Arbitrary Base 5.5 Graphs of Logarithmic Functions and their Properties A The Graphs of y = logax where a>1 B The Graphs of y = logax where 0<a<1 C Relationship between Graphs of Exponential and Logarithmic Functions • Understand the logarithmic functions and their properties. • Recognize the features of the graphs of logarithmic functions. • Understand the relationship between y = logax and y = ax. 5.16 Activity 5.2 Teaching Example (p. 5.30) 5.16 5-Minute Lecture: p. 5.37 Graphs of Logarithmic Functions and their Properties IT Activity 5.1: Properties of graphs of y = logax for a>1 Extra IT Activity: Relationship between the graphs of y = ax and y = logax 2 2 Teaching Guide 5.1 – 5.5 Activity 5.1 Teaching Examples (p. 5.6) 5.1 – 5.5 Teaching Examples (Extra) 5.3, 5.5 4 2 Teaching Objective • Teachers should emphasize that common logarithm is not the only type of logarithms. Its definition and properties can be extended to an arbitrary base a, where a > 0 and a≠1. • Teachers should introduce the base-change formula of logarithms. • Demonstrate how to apply the properties of logarithms to solve related problems. • Teachers may use Activity 5.2 or IT Activity 5.1 to let students explore the properties of the graphs of logarithmic functions. • Teachers should use the tabular and graphical representation of exponential functions and logarithmic functions to discuss their relationship. • The concept of inverse function can be introduced, but its notation and formal definition are not required. • Teachers may use Extra IT Activity to demonstrate the relationship between the graphs of y = ax and y = logax. Exercise 5B (p. 5.15) Level 1: 1 – 14 Level 2: 15 – 30 Rev. Ex. 5 (p. 5.46) Level 1: 14 – 17, 19, 21, 23 – 24 Level 2: 41 – 42, 46 – 47, 50 – 51 Exercise 5C (p. 5.21) Level 1: 1 – 7 Level 2: 8 – 12 Rev. Ex. 5 (p. 5.46) Level 1: 25 – 27 Level 2: 52 – 53 Exercise 5D (p. 5.28) Level 1: 1 – 25 Level 2: 26 – 43 Rev. Ex. 5 (p. 5.46) Level 1: 2 – 4, 6 – 7, 9, 12 – 13, 18, 20, 22, 28 Level 2: 29 – 31, 34, 37, 39, 43 – 45, 48 – 49 Exercise 5E (p. 5.37) Level 1: 1 – 5 Level 2: 6 – 10 Rev. Ex. 5 (p. 5.46) Level 2: 54 – 55 1 5.6 Historical Development of the Concept of Logarithms A The Logarithm Tables B The Anti-logarithm Tables C The Slide Rule • Appreciate the development of the • Teachers can introduce the logarithm concept of logarithms. tables, the anti-logarithm tables and the slide rule. Basic Topical Worksheets Key Stage 3 (S1 to S3): Key Stage 4 (S4 to S6): 40 Percentages (III) 41 Percentages (IV) 80 Common Logarithms NF 81 Logarithms to an Arbitrary Base NF p. 5.41, 5.42