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    Inverse Functions

    f(x) = 1/6 (x^2 - 4x + 24) = 1/6 ((x-2)^2+20) which means the vertex is (2, 10/3) and the axis of symmetry is x=2 Consider some z that exists in the restricted domain of f(x) and then N which doesn't belong to that domain, where f(z)=f(N). Now, by symmetry, (z+N)/2 = 2, since the axis of...
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    Seeking for a Japanese Tutor?

    Miss Wong IS THAT YOU? I don't know if you remember me or not but you took Miss Ogara's class at Baulko back in '07 from memory. Hope everything's going good ! But anyway guys, Miss Wong a.k.a Joan is a REALLY good Jap teacher. She was heaps mad back when she was my teacher and is probably even...
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    Games in the Roundhouse

    OMG All this talk about DDR lol. Dyou know when they open it up? I've been there a couple of times, but it's always closed :( And so I thought that they only opened it up for like, when other people use the uni, like Animania or something... Otherwise I'd probably end up spending my breaks...
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    OH SHIT i totally did not see you message me O_O add me on facebook so i know what you look like...

    OH SHIT i totally did not see you message me O_O add me on facebook so i know what you look like XD (and viceversa...) my email is just,, life92@gmail.com :) weee japanesee
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    Hey, thanks for the add but.. Do I know you? x__x Sorry if I do but have forgotten, I have...

    Hey, thanks for the add but.. Do I know you? x__x Sorry if I do but have forgotten, I have REALLY bad memory~~
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    locus

    Oh my bad. I made a very silly mistake lol. x^2 = 4ay y = x^2 / 4a y' = x/2a At some point (x1,y1) y' = x1/2a Therefore, the gradient of the normal = -2a / x1 y-y1=-2a / x1 (x-x1) Rearranging: 2ax + x1 y = x1 y1 + 2a x1 Subbing (0,a) 0 + x1 a = x1 y1 + 2a x1 0 = x1 y1 + x1 a 0 = x1 (y1 + a)...
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    locus

    lol wth dude. I'm just trying to help out........... But in answer to super.muppy's question about not using parameters, I tried it again and the answer doesn't seem to come out which is pretty weird. I think you could possibly think of this problem as a non-algebraic problem and try to think...
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    locus

    x^2=4ay Focus (0,a) y = x^2 / 4a y' = x / 2a At some point (2ap,ap^2) y' = 2ap / 2a = p Therefore, gradient of normal = -1/p Eqn of normal: y -ap^2=-1/p(x-2ap) py-ap^3=-x+2ap x+py=ap^3+2ap Through (0,a) (focus) ap = ap^3 + 2ap 0 = ap^3 + ap 0 = ap (p^2+1) Therefore, p = 0 only That means...
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    Concavity

    Sometimes even if the second derivative is 0 at a certain point it doesn't necessarily mean its an inflexion. Also Xcelz, that goes for if the first AND second derivative are 0, doesn't necessarily mean its an inflexion. For example, f(x) = x^4 f'(x) = 4x^3 and f''(x) = 12x^2 If you sub x=0...
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    stationary points + points of inflexion

    y = ax^3 + bx^2 - x + 5 y' = 3ax^2 + 2bx - 1 y'' = 6ax + 2b Since it has an inflexion at (1,-2) then y'' = 0 at (1,-2) y'' = 6ax + 2b 0 = 6a(1) + 2b b = -3a Now sub this and (1,-2) into the original equation and you get... -2 = a(1)^3 - 3a(1)^2 - 1 + 5 -2 = -2a + 4 -2a = -6 a = 3 Therefore...
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    Quick Polynomial Question

    P(x)=4x^3+12x^2-15x+4 P'(x)=12x^2+24x-15 = 3 (4x^2+8x-5) = 3 (2x+5)(2x-1) P(1/2) = 0 , therefore the double root is 1/2, or the double factor is (2x-1) By inspection, the last factor must then be (x+4) Therefore the roots are 1/2, 1/2 and -4
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    Volume about the x axis problem

    This is actually obviously very close to the answer. Btw you are missing a pi XD But anyway, as you can see, you integrated from 1=>2, however, if you look at a diagram, there is still a space underneath y=1 in the first quadrant. This is the missing volume that you are leaving out behind...
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    Tutoring MATHS, SCIENCES, and ENGLISH in WESTERN SYDNEY: 1st in Baulko

    LOL I think his jersey name was "Jeganaut" from memory... might want to correct me on that Jega :)
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    =o You might've saw me at the welcome O_O ,, but there were so many people there lol XD But nah...

    =o You might've saw me at the welcome O_O ,, but there were so many people there lol XD But nah, theres 3 others, but one of them didn't come to the welcome...
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    Week 1 Tutes/Lectures

    I think most courses only have Lectures in Week 1. BUT, I know that some courses only start in Week 2, so that means you'll only have lectures next week and then normal classes start from Week 3. Check your timetable for week 2 and 3 and compare.
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    What's wrong with getting 99.90 and doing Optom? hahah XD Yeah I'm doing MATH1141 and hopefully...

    What's wrong with getting 99.90 and doing Optom? hahah XD Yeah I'm doing MATH1141 and hopefully they'll let me change into PHYS1131 ~~ Maybe I'll see you around :)
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    Hey I just read your thread about phys1121 or phys1131. Ahh 1 day before uni and I'm thinking of...

    Hey I just read your thread about phys1121 or phys1131. Ahh 1 day before uni and I'm thinking of changing to phys1131 x__x I'm doing optom too ! :)
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    Tutoring MATHS, SCIENCES, and ENGLISH in WESTERN SYDNEY: 1st in Baulko

    Btw Jega, what ended up not counting? I'm curious o__o
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    Expanding cubic brackets

    This is going to end up pretty long regardless and Trebla's method is pretty good. Alternatively, you can rewrite (a+b+c+d)^3 as [ (a+b) + (c+d) ] ^3 and then treat (a+b) and (c+d) as single terms. So you'll end up with (a+b)^3 + 3 (a+b)^2 (c+d) + 3(a+b) (c+d)^2 + (c+d)^3 Which you can then...
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    Tutoring 2/3 Unit MATHS in HILLS DISTRICT: 99.95 ATAR, 4 state ranks, 1st in Baulko

    Re: Tutoring 2/3 Unit MATHS in HILLS DISTRICT: 99.95 ATAR, 4 state ranks, 1st in Baul Okay. So all I need to say is... this guy is a freak of nature :) I mean, look at all of those state ranks LOL Too bad he didn't get one for Maths though. xP He still owned. Highly recommended ;) I'm sure...
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