Recent content by lektor

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    Differential equation question

    cheers for the help guys, got C = Co*e^(-kt) Would anyone be able to explain the mathematical reason why plotting ln|c| vs t approximating a straight line with experimental data proves this relationship.. cheers.
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    Kinematics: projectiles question

    Given the context of this question being quite large and my main problem being the solving i won't bother with diagrams but anyway the kinematics conditons are Such that i have 10 = (Vcos15)t + 0.5gt^2 1.9 = (Vsin15)t + 0.5gt^2 Can anyone please show me the...
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    Differential equation question

    Kinda lengthy question but bare with me please A 1200 m3 treatment tank is used for treating effluent. The use of a particular form of algae is a major part of this process. It is important that the concentration, C, of algae not fall below 10 gm per litre as the process will not work...
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    Mathematica Mathematical modelling question

    Hey, So, In a question about finding volume in a dome we were Given that V = pi.k(k^2/r - k^2/3r^3 - r/8) And K = m/2pi.p.t Firstly we are asked to obtain an expression for the value of r that maximises the volume of air and rearrange to obtain an equation of the form ar^4 + br^2 + c =...
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    Finding Cable Angle and Components of Tension Force in a Rotational System

    Ok a question from my textbook, mainly selected because I've been having trouble with just this sort of question in general. The cable AB prevents bar OA from rotating clockwise about the pivot O. If the cable tension is 750N, determine the n- and t-components of this force acting on point A...
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    HY 607: Finding the Angle for Resultant Force of Two Forces

    it is simply a diagram showing |.../ |.../ |(-)./ |.../ |./ with the verticle line saying 1400N and the diagonal line saying 800N
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    Solving Proportionality: Cost of Running a Business w/ 18 Employees

    ahah woops, my bad.. So in that case it will be P = x . x^2 P = Kx^3 However when i solve for k the answers are different..
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    HY 607: Finding the Angle for Resultant Force of Two Forces

    with reference to the diagram, at what angle must the 800N force be applied in order that the resultant R of the two forces has a magnitude of 2000N. We were instructed to use the i,j method. So, the forces for Fi = 800sin(-) and Fj = 1400 + 800 cos(-) and the resultant is 2000N. This...
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    Solving Proportionality: Cost of Running a Business w/ 18 Employees

    hrmk so finished that question and was hoping for some help on this next one. In a bookstore, the selling price of a certain dictionary is $x. The total profit ($P) on the sale of the dictionary is partly proportional to the selling price of the dictionary and partly proportional to the square...
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    Solving Proportionality: Cost of Running a Business w/ 18 Employees

    Hi a few questions i want to check my answers for here, 3. Write down an expression, evaluate the constant of proportionality, and answer the question. [Remember to work in SI units. Simplify answers to 1 d.p. only.] (a) The annual cost (C) of running a business is partly constant and...
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    Complex Numbers: Solving Equations with z and zeta?

    Hi, I have no clue how to approach this question, was in my last years final exams. (z^2 + 1)^4 = 1 Find all solutions, where z is a complex number. Tips please?
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    Solving Calc Questions Before Uni: Integrals & Surds

    finally got it, ~_~! Cheers the help on this one schatten~
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    Solving Calc Questions Before Uni: Integrals & Surds

    seriously I've tried this a few times now and the answer they give is still different, can someone please take the time to do the question for me :)i have reviewed viet's technique and what he has done with the sin^3 x is really confusing me.
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    Solving Calc Questions Before Uni: Integrals & Surds

    Great I've got the 2nd and 3rd question, but the first one seems to be a gap in my studies, i have never heard of this odd function concept, could someone please work through the question with labeled steps for me as it may refresh me.
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