Recent content by cineti970128

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    Motor Effect Force

    Source 2 is the correct one.
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    Limiting sum trig

    The first term is 1 and common ratio is -2t/(1+t^2) So use the GP infinite formula a/(1-r) Note that |sinx|<= 1 so you can use day formula.
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    Help? How to improve?

    I SERIOUSLY advice you to drop 3 u and concentrate on your other subjects.
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    FREE notes! 'Belonging: HSC Marker's Tips'!

    Yes please as well^^
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    Applications of Maximisation and Minimisation

    If you want to know how I got this answer, http://community.boredofstudies.org/13/mathematics-extension-1/max-min-question-316578.html
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    Complex Number Question

    (x^2 + y^2)^n Because a^2+b^2 is LHS's modulus squared.
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    complex no.

    Draw a circle with three point A, B, C representing z1, z2, z3. By inspecting the formula, angle at A is 90. Hence using the semi circle angle property, BC must be a diameter through the origin. Since z1 can b anywhere, so by inspecting the modulus |z1+z3| formed by adding z1 and z3 , hence > 0...
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    Max/min question

    With max/min question Always draw a diagram. Let X be a random point on AC and let x be the distance AX Then 0<x<30 including 0 and 30 Then distance BX travelled is using Pythagoras, = (625+x^2)^ 1/2 Hence the time(BX) = {(625+x^2)^ 1/2} ÷ 4 The distance XC travelled is simply 50-x Hence the...
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    Isoperimetric inequality 1.

    That's true. That makes this very hard then:)
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    Isoperimetric inequality 1.

    But you see, the area of a polygon with a fixed perimeter gets maximised as the number of sides increases which gets restricted as a circle with the 1 unit perimeter. A circle is not a polygon yes but it's like the restricting space. The maximum space possible by a fixed perimeter. Ok imagine...
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    Isoperimetric inequality 1.

    Haha... y all these very complicated ideas I think I'm putting forward a very stupid idea but pls don't flame me:) Maximum area of n polygon made possible with a fixed perimeter is a circle- n approaching infinity(Assumption which can be logically deduced) Then this infinitely sided polygon...
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    General Thoughts: Mathematics Extension 1

    You find r when v= 10^(-6)
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    General Thoughts: Mathematics Extension 1

    You integrate from Dr/dt to r= some constant t from i)
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