TRIGONOMETRY II Learning Objectives : Understanding and use the concept of the values of sin θ, kos θ and tan θ (0°≤ θ ≤ 360°) to solve problems.

Learning Outcomes : iii) Verify that, for an angle in quadrant I of the unit circle : Sin θ = y – coordinate ; Cos θ = x – coordinate ; Tan θ = y – coordinate x – coordinate

(iv) Determine the values of a) sine b) cosine c) tangent of an angle in quadrant I of the unit circle.

Do you still remember Pythagoras Theorem ? If yes,who can explain the Theorem ? Sin θ = y h kos θ = x h tan θ = y h X Y H θ y h x

Explain the meaning of unit circle The unit circle is the circle of radius 1 with its centre at the origin. y x y x 1 P(X,Y) OQ θ

Learning Objective Draw and compare the graphs of sine and cosine Learning Outcomes Draw the graphs of sine and cosine for angles between 0° and 360° Compare the graphs of sine and cosine for angles between 0° and 360°

Students are asked to complete the table below for x0°0°30°45°90°135°150°180°210°225°270°315°330°360° y=sin x

 Students are requested to plot y = sin x on a graph paper  Teacher shows the graph y = sin x on power point

SStudents are asked to complete the table below x0°0°30°45°90°135°150°180°210°225°270°315°330°360° G=cos x

 Students are asked to plot the graph y = cos x on a graph paper  Teacher shows the graph y = cos x on power point  teacher discuss with students on the graph y = cos x  At last, teacher shows on power point the combined graph of sin x and cos x.

 Based on the graph y=sin x find the values of x when a) y=-1 b) y=0 c) y=1  Based on the graph y=cos x find the values of x when a) y= -1 b) y= 0 c) y= 1  Based on the combined graph y=sin x and the graph y=cos x find the values of x when sin x = cos x