Recent content by bobmcbob365

first thing that comes to mind is that there is a change from theta on the LHS to theta/2 on the RHS so u could try using double angle formula. and heyyyy, tht means you can get rid of the 1's in both brackets. and then de moivre's from then on

count me in as well

A^2 x^2 =4 not Ax^2 =4

Re: HSC 2013 4U Marathon I'd assume it's meant to be 1-cos(theta)-isin(theta) for the denominator. In which case, I think using double angle formulae will work out.

Re: HSC 2013 4U Marathon haha yeah, dw its 12:30. Heads get all screwy.

Re: HSC 2013 4U Marathon Oh right, not sure if 1st line is right. But I think the question is leading on into expressing z^(2n+1) -1 in (z-z1)(z-z2)(z-z3)... form, where z1, z2, z3... are roots of z^(2n+1)=1

Re: HSC 2013 4U Marathon not quite; but i'm curious as to how you came to that

Re: HSC 2013 4U Marathon oh, factorise into a bunch of quadratic factors

Re: HSC 2013 4U Marathon aaah, I see =/

Re: HSC 2013 4U Marathon a) Find, in modulus-argument form, the roots of the equation z^(2n+1) =1. b) Hence factorise z^2n + z^(2n-1) + ... + z^2 + z +1 into quadratic factors with real coefficients. c) Deduce that 2^n * sin(pi/(2n+1)) * sin(2pi/(2n+1)) * sin(3pi/(2n+1)) ...

Re: HSC 2013 4U Marathon Expressing 957 in its prime factors: 3*11*29 Now, a^2 - b^2 = (a-b)(a+b)=957 So now, take turns making a+b and a-b, from the factors of 957. 1. let a+b=957 a-b=1 2a=958 therefore, a = 479, b=478 2. let a+b=3*11 a-b=29 2a=62 therefore, a=31, b=2 3. let...

Re: HSC 2013 4U Marathon Lol, is the answer a = 479, b=478; c=31, d=2; a=45, b = 42; c=161, d=158

if the dash is supposed to be there for the 3rd q, it's a whole different story.

http://www.boardofstudies.nsw.edu.au/archives/syllabus_hsc/economics-amendments-2011.html Main points to note: - addition of United Nations, OECD, G20 and G7/G8 in 'Trade, financial flows and foreign investment' section (p 31) TOPIC 1 - rewording of the case study requiring study of the...

For (i) Since, you know that Q is P rotated -90 clockwise, you just multiply P by cis (-pi/2)