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    2005 HSC Examiners day

    Would you like to know how the 2005 HSC exams were marked? HSC and SC 2005: Feedback and Advice Saturday 25th February, 2006 Macquarie University – Mason Theatre Free for MANSW members $20 for non-members Program <TABLE cellSpacing=0 cellPadding=5 border=0><TBODY><TR><TD>8:45am...
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    Quicker Method for Long Division of Polynomials

    Yes. That's right. If it's different, a mistake has been made. Students should check their solutions as well as just doing them.
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    Quicker Method for Long Division of Polynomials

    You forgot the remainder. It should be A(x).Q(x)+R, for some number R. If it is a more general divisor, A(x).Q(x)+R(x) where deg(R(x)) < deg(A(x)). The inspection method works for these as well. Just use the last term in Q(x) to get R(x). Also, in your example, I would suggest...
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    induction comment on wiki

    I noticed last night Timbk2 changed the name of the BOS wiki to Biki. That's a funny one! lol.
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    Quicker Method for Long Division of Polynomials

    I can be used for quadratic divisors as well: http://www.purplemath.com/modules/synthetic-division-sgnd.pdf
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    complex numbers question!

    Ask them at your own risk. Most maths teachers don't know much about maths. Ha! Ha! And I bet most of them would not be capable of proving the formula for the square roots of a complex number. Neverthless, here's the MUCH LONGER SOLUTION...
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    Quicker Method for Long Division of Polynomials

    It's called synthetic division. http://www.purplemath.com/modules/synthdiv.htm http://www.purplemath.com/modules/synthdiv2.htm
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    complex numbers question!

    No. x<SUP>4</SUP>-16x<SUP>2</SUP>-15<SUP>2</SUP>=0. This part is right!
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    complex numbers question!

    You can just use the formula and do it in 1 line without mucking about with equations.
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    complex numbers question!

    You missed the square (which I made red): x<sup>4</sup>-16x<sup>2</sup>-15<sup>2</sup>=0.
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    complex numbers question!

    It's not hard to derive. Square both sides: Or alternatively just follow what pLuvia and Riviet said, but in the general case (a bit longer, but it still works).
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    complex numbers question!

    My solution to the Coroneos question used 2 formulae simultaneously. Square roots of a complex number, and quadratic formula. You don't have to use the quadratic formula to solve a quadratic, but it's easier in your example if you do. Likewise, you don't have to use the formula for the...
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    complex numbers question!

    It is in the syllabus. sgn(b) is the sign of b. So if b > 0, sgn(b)=+1, if b < 0, sgn(b)=-1. If b=0, sgn(b)=0, but then there's no need for the formula. Using this formula is a much faster method and so as far as risk is concerned, there's much less chance of making a mistake if you...
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    complex numbers question!

    It's easier if you use the formula:
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    complex numbers question!

    In my solution, w=16-30i.
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