DAILY LESSON LOG Annex to DepEd Order 42, s.2016 School Grade TEN (10) Level: Learning Area: MATHEMATICS Quarter: 3rd Grading FR. GRATIAN MURRAY, AFSC INTEGRATED SCHOOL Teacher Teaching Dates & Time I. OBJECTIVES 1. Content Standards 2. Performance Standards 3. Learning Competencies Objectives BEVERLY N. ALON March, 2023 The learner demonstrates understanding of key concepts of polynomial function. The learner is able to conduct systematically a mathematical investigation involving polynomial functions in different fields. The learner graphs polynomial function. (M10AL-IIa-b-1) a. Describe the behavior of the graph using the Leading Coefficient Test. b. Identify the number of turning points and the behavior of the graph based on the multiplicity of zeros. c. Value accumulated knowledge as means of new understanding. a. Graphs of Polynomial Functions II. CONTENT III. LEARNING RESOURCES A. References pp. 93-105 1. Teacher’s Guide pp. 112-121 2. Learner’s Materials 3. Textbook 4. Additional Materials from Learning Resources (LR) portal B. Other Learning Resources IV. PROCEDURES A. Reviewing previous lesson or presenting the new lesson B. Establishing a purpose for the lesson C. Presenting examples/Instances of the new lesson Find your Match Group the class into 5. Give each group a polynomial function. Have them match the assigned function to them to the given graphs on the board. The group who got the correct answer earns 5 points. Aside from the Intercepts, there are many other things to consider when we draw the graph of a polynomial function. These are some other things that we need to take into consideration; a. multiplicity of roots. b. behavior of the graph c. number of turning points Illustrative Examples: 1. Describe the behavior of the graph of f(𝑥) = (𝑥 + 1)2 (𝑥 + 2)(𝑥 − 2)(𝑥 − 3). a. x- and y-intercepts: x-intercepts:−2,−1,−1,2, 3 y-intercept: 12 The graph will intersect the x-axis at (−2,0),(−1,0),(2,0), (3,0) and the y-axis at (0,12). b. multiplicity If 𝑟 is a zero of odd multiplicity, the graph of (𝑥) crosses the x-axis at r. If 𝑟 is a zero of even multiplicity, the graph of (𝑥) is tangent to the xaxis at 𝑟. Since the root -1 is of even multiplicity 2, then the graph of the polynomial is tangent to the x-axis at -1. c. behavior of the graph: The following characteristics of polynomial functions will give us additional information. The graph of a polynomial function: i. comes down from the extreme left and goes up to the extreme right if n is even and 𝑎𝑛 > 0 ii. comes up from the extreme left and goes up to the extreme right if n is odd and 𝑎𝑛 > 0 iii. comes up from the extreme left and goes down to the extreme right if n is even and 𝑎𝑛 < 0 iv. comes down from the extreme left and goes down to the extreme right if n is odd and 𝑎𝑛 < 0 For additional help, we can summarize this in the figure: n is even n is odd an>0 an<0 If the polynomial function 𝑃(𝑥) = (𝑥 + 1)2(𝑥 + 2)(𝑥 − 2)(𝑥 − 3) is written in the standard form then we have 𝑃(𝑥) = 𝑥5 − 𝑥4 − 9𝑥3 + 𝑥2 + 20𝑥 + 12 We can easily see that this is a 5th degree polynomial. Thus, 𝑛 is odd. The leading term is 𝑥5, 𝑎𝑛 = 1 and 𝑎𝑛 > 0. Therefore the graph of the polynomial comes up from the extreme left and goes up to the extreme right if n is odd and 𝑎𝑛 > 0 d. number of turning points: Remember that the number of turning points in the graph of a polynomial is strictly less than the degree of the polynomial. Also, we must note that; i.Quartic Functions: have an odd number of turning points; at most 3 turning points ii.Quintic functions: have an even number of turning points, at most 4 turning points iii.The number of turning points is at most (𝑛 − 1) For our graph to pass through the intercepts (−2,0), (2,0), (3,0) and tangent at (−1,0), there will be 4 turning points. 2. Describe the behavior of the graph of 𝑦 = 𝑥4 − 5𝑥2 + 4 a. x- and y-intercepts The polynomial in factored form is 𝑦 = (𝑥 − 1)(𝑥 + 1)(𝑥 − 2)(𝑥 + 2) The roots(x-intercepts) are 1,−1, 2 and −2. The y-intercept is 4 The graph will intersect the x-axis at (−2,0),(−1,0),(2,0), (1,0) and the y-axis at (0,4). b. multiplicity There are no roots of even multiplicity. c. behavior of the graph: 𝑛 = 4 and is even Since 𝑛 is even and 𝑎𝑛 >0, then the graph comes down from the extreme left and goes up to the extreme right. d. turning points There are 3 turning points. D. Discussing new concepts and practicing new skills # 1 1. Are the intercepts enough information for us to graph polynomials? 2. How can we describe the behavior of the graph of a polynomial function? 3. E. Discussing new concepts and practicing new skills # 2 Is it possible for the degree of function to be less than the number of turning points? Find the following then describe the behavior of the graph of 𝑝(𝑥) = 𝑥3 − 𝑥2 − 8𝑥 + 12 a. leading term: ______ b. behavior of the graph: ____________________ ( 𝑛 is odd and 𝑎𝑛 > 0) c. x-intercepts: ________ the polynomial in factored form is 𝑦 = (𝑥 − 2)2(𝑥 + 3) d. multiplicity of roots:_____ e. y-intercept:_________ f. number of turning points: F. Developing mastery (leads to Formative Assessment 3) Describe the graph of the following polynomial functions: 1. 𝑦 = 𝑥3 + 3𝑥2 − 𝑥 − 3 2. 𝑦 = −𝑥3 + 2𝑥2 + 11𝑥 - 12 G. Finding practical application of concepts and skills in daily living GROUP ACTIVITY Describe the graph of the following polynomial functions: 1. 𝑦 = 𝑥3 − 𝑥2 − 𝑥 + 1 2. 𝑦 = (2𝑥 + 3)(𝑥 − 1) (𝑥 − 4) H. Making generalizations and abstractions about the lesson Things to consider before we draw the graph of a polynomial function. a. x- and y- intercepts b. multiplicity of roots If 𝑟 is a zero of odd multiplicity, the graph of (𝑥) crosses the x-axis at r. If is a zero of even multiplicity, the graph of (𝑥) is tangent to the xaxis at 𝑟. c. behavior of the graph The following characteristics of polynomial functions will give us additional information. The graph of a polynomial function: i. comes down from the extreme left and goes up to the extreme right if n is even and 𝑎𝑛 > 0 ii. comes up from the extreme left and goes up to the extreme right if n is odd and 𝑎𝑛 > 0 iii. comes up from the extreme left and goes down to the extreme right if n is even and 𝑎𝑛 < 0 iv. comes down from the extreme left and goes down to the extreme right if n is odd and 𝑎𝑛 < 0 For additional help, we can summarize this in the figure: n is even n is odd an >0 an< 0 I. Evaluating learning J. Additional activities for application or remediation d. number of turning points: Remember that the number of turning points in the graph of a polynomial is strictly less than the degree of the polynomial. Also, we must note that; i.Quartic Functions: have an odd number of turning points; at most 3 turning points ii.Quintic functions: have an even number of turning points, at most 4 turning points iii.The number of turning points is at most (𝑛 − 1) For the given polynomial function 𝑦 = −(𝑥 + 2) (𝑥 + 1)4(𝑥− 1)3, describe or determine the following. a. leading term b. behavior of the graph c. x-intercepts d. multiplicity of roots e. y-intercept f. number of turning points A. Follow Up For the given polynomial function 𝑦 = 𝑥6 + 4𝑥5 + 4𝑥4 − 2𝑥3−5𝑥2 − 2𝑥, describe or determine the following: a. leading term b. behavior of the graph c. x-intercepts d. multiplicity of roots e. y-intercept f. number of turning points g. sketch B. Study: Graph of the function 𝑦 = 𝑥6 + 4𝑥5 + 4𝑥4 − 2𝑥3−5𝑥2 − 2𝑥 Prepared by: BEVERLY N. ALON Teacher I Checked by: RICARDO CAMINIAN Head Teacher 1