DUE 26 AUGUST 2026
QUESTION 1: FORUM 5
QUESTION 2: LESSON 7 – TRIGONOMETRY
2.1 Self-Assessment 7.1
Question 2a: cos 150° (3 marks)
cos 150° = cos(180° - 30°) = -cos 30° = -√3/2
(UNISA, 2026, Lesson 7, p. 186) – shows reduction formula for cos(180° - θ)
(Serra, 2008, p. 185) – quadrant values and reduction
, Question 2b: sin(-45°)
: sin(-45°) = -sin 45° = -√2/2
(UNISA, 2026, Lesson 7, p. 187) – negative angle reduction formula
(Serra, 2008, p. 184) – special angle table
Question 2c: tan 480°
tan 480° = tan(480° - 360°) = tan 120° = tan(180° - 60°) = -tan 60° = -√3
(UNISA, 2026, Lesson 7, p. 187) – quadrant III and IV reduction formulae
Question 2d: [sin(180° + x) × cos 330° × tan 150°] / sin x
sin(180° + x) = -sin x
cos 330° = cos(360° - 30°) = cos 30° = √3/2tan 150° =
tan(180° - 30°) = -tan 30° = -1/√3
[(-sin x) × (√3/2) × (-1/√3)]
/ sin x= [(-sin x) × (-1/2)]
/ sin x
= (sin x/2) / sin x = 1/2