Detailed Lesson Plan in TrigonometryI. Objectives: At the end of the lesson, student should be able to: 1. Define the six trigonometric ratios of an acute angle of triangle (cognitive). 2. Explain why the six trigonometric ratios are trigonometric functions (affective). 3. Demonstrate the six trigonometric functions to the class (cognitive).II. Subject matter: Topic: The Six Trigonometric Functions References: Deauna, Melecio C. and Lamayo, FloritaC.Basic Trigonometry for Secondary Education (1998); pp. 48-52Orines, Fernando B., Esparrago, Mirla S. and Reyes Jr., Nestor V., Advanced Algebra, Trigonometry and Statistics (2nd Edition); pp.518-523 Materials: Hunt-a-word puzzle (in manila paper) Cut-out trianglesIII. Learning Activities Teacher’s Activity Students’ Activity1. Daily Routine “Good afternoon, class “Good afternoon too, ma’am”Alyssa will you lead us in prayer Alyssa will lead the prayerThank you, Alyssa. You may now take Students will sit downyour seat Ms. Charlayne, will you kindly check who’spresent and who’s absent for today.2. Review Before we proceed to our new lesson, let’s “It’s all about on how to convert Radians tohave a quick review. What was our degree.”previous lesson”That’s right. So how do we convert angle “ In converting the angle measure frommeasure form degree to radians and degree to radians we use the andradians to degree” radians to degree we use the .3. Motivation “ Now that you know how to convert degreeto radians and radians to degree, let’s Students will listen have a simple game, class. (Showinga hunt-a-word puzzle). In one minute I Students will look for the wordswant you to find the six words below.“Have you found them all?” “Yes ma’am!”“ I want the group of JC to show us thewords below.Can you stand up and box The group of JC will box the wordsthe words below?”“Thank you. You may now take your seat.” The group of JC will take their seat
B. Procedures1. Presentation Have you already encounter these Not yet, ma’am.words.Today we will be discussing the six Students will listentrigonometric functions. 2. Abstraction(Showing the cut out triangles)We have a right triangle ABC with theright angle at C and the two legs a andb and c the hypotenuse. With respect Students will listento the acute angle θ, side a is the sideopposite to θ, the b would be the sideadjacent to θ and the c is thehypotenuse.(Showing the six trigonometricfunctions) This are the six trigonometric functions of an acute angle. Before we Students will read the definitions. find the trigonometric functions of our triangle, let us read first the definitions of it. Let us first find the sinθ, firstwe need The side a is the side opposite to find the side opposite and the and the side b is the side hypotenuse.hypotenuse of the triangle.What is the side opposite of this triangle and the hypotenuse?To label it, we will write .That’s how we find sin θ.” Now to findcos θ, we need to find theside adjacent and the hypotenuse of Cos θ =the triangle.So how we will label the cos θ?“Very good. In tan θ, we need the side Tan θ = opposite and the side adjacent. How we will be label it?“For the remaining three functions, thesethree are the opposites to the firstfunctions. The cot θ is opposite tothe function of tangent where the Cot θ = cot θ is side adjacentover sideopposite. How about the cot θ, how wewill label it?In sec θ and csc θ, their opposites are the
cos θ and sin θ. So our sec θ = and the csc θ = . That’s how we find the six trigonometric functions. We will only follow the definition of this trigonometric functions. Did you get on how to find the Yes, ma’am trigonometric functions? Do you have any questions? No ma’am.3. Applications (Showing an illustrated example): 1 ө 2 √3Let’s have another example. Find the six Student will raise his/her hand function of the triangle. Who would like to find the first three functions? Sine = Cosine = Tangent=Very good. How about the last three Student will raise his/her hand functions? Cotangent = Secant = Cosecant =IV. Evaluation Find the six trigonometric functions of the triangle. 1. 13 12 ө 5
2. 8 17 15 ө3. 6 ө 10 8V. Assignment Memorize the six trigonometric functions we will be having a short quiz for the next meeting.