Skip to content

Course home

Sign up

Radians

EasyMediumHard
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143
Question 44

When x x\,x is small, using tan⁡x≈x+x33\displaystyle \tan x \approx x + \frac{x^3}{3}tanx≈x+3x3​ and cos⁡x≈1−x22\displaystyle \cos x \approx 1 - \frac{x^2}{2}cosx≈1−2x2​,

a.

show that tan⁡(3x)cos⁡(4x)\tan (3x) \cos (4x)tan(3x)cos(4x) can be approximated by 3x−15x33x - 15x^33x−15x3

[3]
b.

Hence, approximate the value of tan⁡(0.3)cos⁡(0.4)\tan (0.3) \cos (0.4)tan(0.3)cos(0.4)

[2]
c.

Calculate the percentage error in your approximation, giving your answer to 3 significant figures

[1]
Markscheme

Radians Questions

  1. A Level
  2. /Maths
  3. /Radians

278 exam-style questions on Edexcel A Level Maths Radians, covering 5.1 Radian Measure, 5.2 Arc Length, 5.3 Areas of Sectors and Segments, 5.4 Solving Trigonometric Equations, and 5.5 Small Angle Approximations. Each one has a worked solution and a mark scheme showing where the marks go.

Question bank