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    A...Question :P

    yeah realised that just after i posted it. hence the deletion
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    Multiple Choice

    no projectiles with angles of @ and 90-@ will have the same range.
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    complex....

    do you not also have to take the 5th root of the modulus? EDIT: sorry ignore me. i didnt read the post carefully enough
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    Who plans to continue doing maths at uni?

    i'm going to major in pure maths at sydney anyone else going to sydney? you can do maths though the adv science or just the normal Bsc course and even transfer to adv maths later is you want.
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    q4 biased toward 4 unit

    you dont need the substitution its a very basic 3u concept that cos x is the derivative of sin x. it is only a matter of applying the function of a function rule in reverse.
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    N-nomial expansion

    there is also a really cool pascals triangle like pattern that developes in three dimensional for for a tri-nomial, 4 dimensional for quad-nomial........ and n-dimensional for an n-nomial. you can then apply the formula you derived and find a number at any point in the n-dimensional pyramid...
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    Complex Numbers + Induction

    1) assume true for n = k consider n = k + 1 we must prove: __ __ _____ ________________ z1 + z2 + ... + z(k+1) = z1 + z2 +... + z(k+1) __ __ __ ______________ (nB: z1 + z2 + ... + zk = z1 + z2 + ... + z k)...
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    Timing in the MX2 exam

    you have to be careful though because the areas under the x axis are negative. if you just add the areas you'll get 5 instead of 3
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    Timing in the MX2 exam

    because the integral of x is x^2/2 you can ignore the absolute value signs as the out come will be positive anyway therefore int ( 2 - abs(x) ) from -3 to 3 2 int ( 2 - x ) from 0 to 3 (even function) = 2[2x - x^2/2 ] from 0 to 3 = 2[(6 - 9/2) - (0)] = 2[3/2] = 3...
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    Question

    it think jago ment he checked your answer by using gaphamatica himeself
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    a probability question - past HSC

    The probability that the prize will never be won limits to zero therefore the probability that it will be won eventually after its 25th time will be equal to the probability that it will not be won on the first 25 times. Your approch with binomial probability is wrong even if the question...
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    circle geometry questions

    yes but equal angles at the circumfrenced also subtend equal chords. this is important it will come up a lot
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    circle geometry questions

    4a) let CBA = x therefore ADC = 180 - x (cyclic quad, supp opp angles) ADC is isosolese therefore DAC = ACD = x/2 DBC = DAC = x/2 (angle subyended byh the same seg.) BCD is isosolese therefore DBC = BDC = x/2 therefore triangles BCD and ADC are congruent (AAS)...
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    Mod-arg identities/proofs

    sub in r(cos@ + isin@) and then expand and simplify you will have to use the cosine and sine addition of angle laws.
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    circle geometry questions

    i wont actually do 2 and 3 i dont have time but for 2: trynd draw a fairy accurate diagram so that you can see wich side of the centre cirtain chords lie and which angles are acute/obtuse etc use isosoles triangles formed by two radii and a chod and angle sums of trangles and also the fact...
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    circle geometry questions

    first one: BEA = ADC (subtented by equal chords AB and AC respectively) BEA = EAD (alternate angles on parallel lines BE and AD) therefore: ADC = EAD (both equal BEA) ADC and EAD are therefore equal and alternate angles of the lines AE and CD there fore Ae is parallel to CD
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    pendulum questions

    for 2 ii: by drawring the forces in for particle A we can see that: T = mlw^2 (7) where T is the tension force which is the same the whole way through the string and therefore is the same for particle B. l is the radius. from (4): T(x) = MrQ^2 from the diagram we...
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    pendulum questions

    for 2 i: by drawring the forces accociated with particle B we can see that: T(y) + N = Mg (1) where T(y) is the vertical component of the Tension force T. we can also see that T(y) = T cos@ (2) T(x) = T sin@ (3) and that: T(x) = MrQ^2 (4)...
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    Question

    at the point P: sin @ = cos^2 @ where @ is the x coordinate at P y = tan x y' = sec^2 x at point P: sec^2 @ = sin^-1 @ (cos^2 @ = sec^2 @) therefore m1 = sin^-1 @ y = cos @ y' = -sin @ therefore m2 = -sin @ m1 x m2 = sin^-1 @ x -sin @ = -1...
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    Cssa Trial Exam

    im pretty sure it was 4/7 or 7/4 or something
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