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    If you live near Epping, I'd be delighted to provide you face-to-face 1-on-1 tutoring in 4U...

    If you live near Epping, I'd be delighted to provide you face-to-face 1-on-1 tutoring in 4U Maths. Message me first if interested.
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    Easy Integral Question

    I "invented" this method (let's for now call it the "Drongoski Method"). A 2-hour lesson would be sufficient for an introduction to my method. So far, I've attracted no interest. I think they don't know what my approach is all about. But I believe it to be a very powerful, intuitive and very...
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    inequality problem

    Ok. Posted it especially for your benefit, since you indicated multiple times you could not follow my explanation.
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    inequality problem

    But is this version of any help. Do you now understand my solution?
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    inequality problem

    A picture is worth a thousand words.
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    Easy Integral Question

    Hello again, clarifying my approach to integration..
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    Easy Integral Question

    Hello Hello Hello.
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    cooked integration

    Wish I was half as smart as you at your age. Good on you.
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    cooked integration

    Are you in Year 9 only?
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    cooked integration

    \int \frac {ln ([3x^5 + 3]^{5x^4})}{x^5 + 1}dx \\ \\ = \int \frac {5x^4[ln(x^5 + 1) + ln 3]}{x^5 + 1}dx \\ \\ = \int ln(x^5 + 1)\cdot \frac {5x^4}{x^5 + 1} dx + ln 3\int \frac {5x^4}{x^5 + 1} dx \\ \\ = \int ln(x^5 + 1)dln(x^5 + 1) + ln3\int \frac {1}{x^5 + 1}d(x^5 + 1) \\ \\ = \frac...
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    inequality problem

    OK. Say you take x = 5.7 say. Then this number is |5.7 + 1| = 1 + 5.7 = 6.7 away from the number -1, and |5.7 -5| = 0.7 away from the number 5; so it is = the constant 6 plus 2 x 0.7 from the 2 numbers. Remember, any x outside the closed interval [-1,5] is 6 + twice its distance from the nearer...
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    inequality problem

    Say you choose any x between -1 and 5, x = 2, say. then |x+1| + |x-5| = |2+1| + |2 - 5| = 6. Choose another such number, say x = -0.7; then |x+1| + |x-5| = |-0.7 + 1| + |-0.7 -5| =0.3 + 5.7 = 6 (again). If you choose x = -3 (which is more than 0.5 to the left of -1), then |-3+1| + |-3-5| = 2 + 8...
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    inequality problem

    Follow what i said. Draw a line and mark off -1 and 5. any number x between and including -1 and 5 will have |x+1| + |x-5| = 6 (a fixed sum - so we need at least 1 more for this sum) So x must be outside this interval; x now only needs to be more than 0.5 beyond the 2 numbers -1 and 5; i.e. at...
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    inequality problem

    To me graphing is easier like this: Draw the number line and mark off the 2 numbers "-1" and "5". The distance between these 2 numbers = 5-(-1) = 6. Now read the inequality this way: the distance of the number x from "-1" plus the distance of x from the number "5" is greater than 7. Now x...
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    justifying a trig for inequality

    Yes! For someone doing MX2, your grasp of the fundamentals of trigonometry needs to be better.
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    justifying a trig for inequality

    It is. It is always true that: cos(\pi -\theta) = -cos \theta whatever the value of theta.
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    euler's form

    No.
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    Sequence induction proof

    In outline as LaTeXing is so tedious. \therefore b_2 = b_{1+1} = b_1(b_1 + 1) = 1(1+1) = 2\\ \\ \therefore b_2 = 2 = 1 + \sum ^1 _{r=1} b_r ^2 = 1 + 1^2 Therefore true for k = 1. Now assume true for n = k (k >= 1) \therefore b_{k+1} = 1 + \sum ^k _{r=1} b_r ^2 \\ \\ b_{k+2} = b_{k +1}(b_{k...
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    Sydney uni removing advanced maths prerequisites

    Australia likes to boast about world-class universities. All those university ranking bodies like the Times Higher Education World University rankings that appear annually shouldn't be taken too seriously. To give a bonus point for a Band 3 in (the so-called - what a misnomer) Advance Maths is a...
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    Sydney uni removing advanced maths prerequisites

    I recall having a chat with a stranger about 10 years ago who told me he was doing Electrical Engineering at USyd, but did not study Physics for his HSC. They let him do it. May well have eventually completed his B Eng(Electrical). Miracles do happen! Scott Morrison is right after all.
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