Mathematics in Education and Industry Warm Up… Warm Up… Find all 4 real values of x that satisfy (X-5) x2- 4 =1 AEA Session 1: Constructing a beautiful, clear, concise argument: the proper use of notation • how to write mathematics in “good style” • understanding key symbols and using them correctly • ‘exact’ values • reasoning, conciseness and clarity Warm Up Common symbols with which you should be familiar: “implies”, “means that” – very useful for linking statements together and can help avoid the tendency to overuse the “equals” sign “not equal to” – hardly ever used by students but surprisingly useful “identically equal to” – so signifies an identity, something which is true for all values, as opposed to an equation “approximately equal to” “because” “therefore” “the SUM of” (“sigma”) – eg: arcsin x sin 1 x nx n n 1 equivalent statements for “inverse sine”, ie: “the angle whose sine is …” Exact values: Fill in the table! sin 0 6 4 3 2 cos tan Exact values: Learn these (or know how to quickly derive them) 0 6 4 3 2 sin cos tan 0 1 0 1 2 1 2 3 2 1 3 1 3 2 1 2 1 2 1 0 3 AEA Specimen Paper Q4 8 Marks The notation in the printed answer looks daunting – it is meant to be! But this question relies only on standard co-ordinate geometry techniques. AEA June 2004 Q2 2 Marks 2 Marks This question makes use of the “sigma” notation and requires a fairly standard application of the binomial theorem AEA June 2007 Q3 (a) Solve, for 0 ≤ x < 2π, cos x cos 2x 0 (b) 5 Marks Find the exact value of x, x ≥ 0, for which arccos x arccos 2 x 2 6 Marks This question uses the “arc” notation, meaning “inverse cos” or “the angle whose cosine is ..” (alternative symbol cos -1 x); you should aim to answer the first part as concisely as possible whilst still maintaining clarity and reason. The second part is a bit more of a challenge …