Ask Singapore Homework?
Upload a photo of a Singapore homework and someone will email you the solution for free.
Question
secondary 3 | A Maths
One Answer Below
Anyone can contribute an answer, even non-tutors.
help pls
Date Posted: 3 years ago
Views: 450
a = 3/2 , b = 3/2 , c = -½
P (2π/3, -2)
-2 < k < 1
a cos bx + c = -1
3/2 cos (3/2 x) - ½ = -1
3/2 cos (3/2 x) = -½
cos (3/2 x) = -½ ÷ 3/2
cos (3/2 x) = -⅓
Basic angle = cos-¹ (⅓) ≈ 1.231 (in radians)
Since the cosine is negative, look at the 2nd and 3rd quadrant.
Since 0 ≤ x ≤ 2π, then 0 ≤ 3/2 x ≤ 3π
3/2 x = π - 1.231, π + 1.231, 3π - 1.231
x = ⅔(π - 1.231) , ⅔(π + 1.231) , ⅔(3π - 1.231)
x ≈ 1.274, 2.915, 5.463
x = 1.27, 2.92, 5.46 (3 s.f)
3/2 cos (3/2 x) - ½ = -1
3/2 cos (3/2 x) = -½
cos (3/2 x) = -½ ÷ 3/2
cos (3/2 x) = -⅓
Basic angle = cos-¹ (⅓) ≈ 1.231 (in radians)
Since the cosine is negative, look at the 2nd and 3rd quadrant.
Since 0 ≤ x ≤ 2π, then 0 ≤ 3/2 x ≤ 3π
3/2 x = π - 1.231, π + 1.231, 3π - 1.231
x = ⅔(π - 1.231) , ⅔(π + 1.231) , ⅔(3π - 1.231)
x ≈ 1.274, 2.915, 5.463
x = 1.27, 2.92, 5.46 (3 s.f)
See 1 Answer
360 Tutoring Program