MATHEMATICS RESOURCE PACKAGE QUARTER I Week 1 Subject: GENERAL MATHEMATICS Date: ________________ Grade Level: 11 Day: 2 (Lesson 2) Content Standard The learner demonstrates understanding of key concepts of functions. Performance Standard The learner is able to accurately construct mathematical models to represent real-life situations using functions. Learning Competency M11GM-Ia-2 The learner evaluates a function. I. OBJECTIVES Knowledge: Skills: Affective: II. CONTENT The learner: Finds the function value of f(x) at a specific value of x; Evaluates functions given a specific value of x; Shows accuracy in evaluating a function. Evaluating Functions III. LEARNING RESOURCES A. References 1. Teacher’s Guide Pages 2. Learner’s Materials Pages 3. Textbook Pages 4. Additional Materials 5. Learning Resources (LR) portal B. Other Learning Resources TG for SHS General Mathematics, pp. 11-13 LM in General Mathematics, pp. 10-12 General Mathematics by Orland Oronce Series 2016 Slide Decks on the Topic Teacher’s Guide and Learner’s Material General Mathematics, Diwa Publishing, Senior High School Series. 2016 IV. PROCEDURES A. Reviewing or presenting the new lesson Recall the definition of a function. Prepared by: MERCYDITHA D. ENOLPE SHS Teacher (Zamboanguita-JMLMHS) MATHEMATICS RESOURCE PACKAGE B. Establishing a purpose for the lesson Ask: What would happen if a sack of rice grains is poured into the opening of a working milling machine? C. Presenting examples of the new lesson Make a discussion about evaluating a function and say: If one thinks of functions as a function machine, evaluating a function is analogous to providing our machines with a valid input. Evaluating a function means replacing the variable in the function, in this case x, with a value from the function’s domain and computing for the result. To denote that we are evaluating f at a for some a in the domain of f, we write f(a). If one thinks of functions as a machine, evaluating a function is similar to providing our machines with a valid input. D. Discussing new concepts and practicing new skills #1 (See Example TG, p. 12). Take for example, (a) evaluate f ( x) 2 x 1 at x 1.5 . E. Discussing new concepts and practicing new skills #2 Ask: What is the function value of f as defined in Example 1 if evaluated at f (3x 1) ? F. Developing Mastery Step 1. f ( x) 2 x 1 Given Step 1. f (1.5) 2(1.5) 1 By substitution Step 2. f (1.5) 3.0 1 Closure Property of Multiplication Step 3. f (1.5) 4 Closure Property of Addition Step 4. Thus, the function value is 4. Proceed to Example 2 on the same page. Or you may opt to change the values of x to find the function values. Below is the thorough discussion of the solution. Step 1. f ( x) 2 x 1 Given Step 2. f (3x 1) 2(3x 1) 1 by Substitution Step 3. f (3x 1) 6 x 2 1 Distributive Property Step 4. f (3x 1) 6 x 1 Closure Property of Addition Step 5. Thus, the function value is 6x 1 . Let the learners work with a partner. Assign the problem below. The solution is provided for you. The teacher will have to mill around to facilitate the group activity. Call a representative to discuss the solution in the class. ( A classroom reward system could be used to further encourage and motivate the learners to Prepared by: MERCYDITHA D. ENOLPE SHS Teacher (Zamboanguita-JMLMHS) MATHEMATICS RESOURCE PACKAGE participate in the activity, say the first five groups earns extra points.) Evaluate q( x) x 2 2 x 2 at q (2 x 3) . Solution: Step 1. q( x) x 2 2 x 2 Given Step 2. q(2 x 3) (2 x 3) 2(2 x 3) 2 by Substitution Step 3. q(2 x 3) 4 x 2 12 x 9 4 x 6 2 Squaring, DPMA Step 4. q(2 x 3) 4 x 2 8x 5 Combining similar terms Step 5. Thus, the function value is 4 x 2 8 x 5 . Seatwork: 2 G. Finding practical applications of concepts and skills in daily living 1. Mark started selling snacks in the nearby school. In one day he spends P200 for rent and P25 for each snack item he prepares. His expenses in a single day can be expressed as the function C(x) = 25x + 200, where x is the number of items and C(x) is his daily expenses in pesos. How much are his expenses if he prepares 100 snack items? 150 snack items? Answer: P2,700 and P3,950, respectively. 2. The function for the height of an object dropped from 100meter tall platform at time t seconds is approximated by s(t) = 5(𝑡 2 + 100. 𝑇ℎ𝑖𝑠 𝑓𝑜𝑟𝑚𝑢𝑙𝑎 𝑖𝑠 𝑏𝑎𝑠𝑒𝑑 𝑜𝑛 𝑎𝑛 𝑎𝑝𝑝𝑟𝑜𝑥𝑖𝑚𝑎𝑡𝑒𝑑 𝑣𝑎𝑙𝑢𝑒 𝑓𝑜𝑟 𝑡ℎ𝑒 𝑎𝑐𝑐𝑒𝑙𝑒𝑟𝑎𝑡 100𝑚 𝑑𝑢𝑒 𝑡𝑜 𝑔𝑟𝑎𝑣𝑖𝑡𝑦. ) What is the height of the object after 2 𝑠2 seconds? after 4 seconds? Answer: 80 and 20 meters, respectively. H. Making Generalizations and abstractions about the lesson I. Evaluating learning Ask: How is evaluating a function done? Evaluating a function can be done replacing the variable in the function, in this case x, with a value from the function’s domain and computing for the result. To denote that we are evaluating f at a for some a in the domain of f, we write f(a). See attachment. Prepared by: MERCYDITHA D. ENOLPE SHS Teacher (Zamboanguita-JMLMHS) MATHEMATICS RESOURCE PACKAGE J. Additional Activities for application or remediation For remediation, assign learners to pick 2 problems that they did not worked on in the previous activity found in part I. Peer tutoring is desired for this purpose. For enrichment, assign Seatwork 5 on p. 11. The same rubric should be used for grading the learners’ outputs. V. REMARKS VI. REFLECTION A. No. of learners who earned 80% in the evaluation B. No. of learners who require additional activities for remediation C. Did the remedial lessons work? No. of learners who have caught up the lesson D. No. of learners who continue to require remediation E. Which of my teaching strategies worked well? Why did these work? F. What difficulties did I encounter which my principal and supervisor help me solve? A. ____ No. of learners who earned 80% in the evaluation B. ____ No. of learners who require additional activities for remediation C. Did the remedial lessons work? _____ No. of learners who have caught up the lesson. D. ___ No. of learners who continue to require remediation Strategies used that work well: ___ Group collaboration ___ Games ___ Poweerpoint presentation Answering preliminary activities/exercises ___ Discussion ___ Differentiated Instruction ___ Case Method ___Role Playing /Drama ___ Think-Pair-Share (TPS) ___ Doscivery Method ___ Rereading of Paragraphs/Poems/Stories ___ Lecture Method Why? ___ Complete Ims ___ Availability of Materials ___ Pupil’s eagerness to learn ___ Group member’s cooperation in doing their tasks ___ Bullying among learners ___ Equipment (AVR/LCD) ___ Learner’s behavior/attitude ___ Science/Computer/Internet Lab ___ Colorful Ims ___ Additional Clerical Works ___ Unavailable Technology ___ Reading Readiness G. What innovation or localized I used/discover which I wish to share with other teacher? Prepared by: MERCYDITHA D. ENOLPE SHS Teacher (Zamboanguita-JMLMHS) MATHEMATICS RESOURCE PACKAGE EVALUATION WORKSHEET No. ___ 1. Evaluate the following functions at x = 3. a) f(x) = x – 3 b. g(x) = 𝑥 3 − 3𝑥 + 5 3 c. h(x) = √𝑥 3 + 𝑥 + 3 d. p(x) = 𝑥 2 +1 𝑥−4 𝑥+3 2. For what values of x can we not evaluate the function f(x) = 𝑥 2 −4. Prepared by: MERCYDITHA D. ENOLPE SHS Teacher (Zamboanguita-JMLMHS) MATHEMATICS RESOURCE PACKAGE ANSWER KEY 1. 2. The domain of the function is given by {𝑥: 𝑥 ∈ ℝ, 𝑥 ≠ ±2} Prepared by: MERCYDITHA D. ENOLPE SHS Teacher (Zamboanguita-JMLMHS)