CAPE Pure Mathematics Unit 1 · May/June 2005 · Paper 2 · Question 4(b)(i)
Show that cos 3θ = 4cos³θ - 3cosθ.
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Practise this questionOther parts of this question
- 4(a)(i)Express the arc length ABC in terms of π.[1 mark]
- 4(a)(ii)a)Hence, show that r = 7/6.[3 marks]
- 4(a)(ii)b)If h cm is the height of the cone, then the exact value of h is (7√35)/6.[2 marks]
- 4(b)(ii)By using the identity in (b)(i) above, find the value of θ, 0 ≤ θ ≤ π/2, such that a and b are perpendicular.[5 marks]
- 4(c)Find the modulus of the complex number z = (25(2+3i))/(4+3i).[4 marks]
More practice: the rest of this paper · more Trigonometric Functions, Identities and Equations questions · all CAPE Pure Mathematics Unit 1 past papers