Recent content by ebola_virus

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    Obtaining the curve through envelope?

    I was looking through how to obtain the curve if you have a family of straight lines.. and I found that you 'obtain the envelope' promptly looking this up i got:The form of envelope treated here is a manifold that manages to be tangent to some point of each member of a family of manifolds...
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    Forces on systems in equilibrium

    set up two retort stands to support a pulley and a pivot and arrange the apparatus as shown in the diagram attached... and I'm kinda stuck as to how to find the mass of the beam in this instance? Could you give me any starting references i can work along with; torque is involved, but i just...
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    Paper folding and mathematics?

    I was reading on wikipedia when i stumbled through this article on paper folding which said: Paper folds can be constructed to solve square roots and cube roots; fourth-degree polynomial equations can also be solved by paper folds. The full scope of paper-folding-constructible algebraic...
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    Proving a+b+c=abc with Inverse Trig Functions

    er, i guess i got it hehe i got it that makes more sort of. systematic sense. using the double angle for tan thing tan [a + b] = tan (a) + tan (b) --------------- 1 - tan(a)tan(b) state that tan (a) = A tan (b) = B...
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    Proving a+b+c=abc with Inverse Trig Functions

    a teacher wrote on the board tan-1(a) + tan-1(b) + tan-1(c) = pi [they are inverse trig functions btw, not the recipricol 1/tanx = cotx] hence prove that a + b + c = abc wow. do you have any idea where i can start? thanks. I've been uttered clueless.
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    Amplitude of 3-kg Pendulum 2m Arc 21.4°

    A pendulum has a mass of 3-kg, a length of 2 meters and swings through a (half)arc of 21.4 degrees. What is its Amplitude to the nearest centimeter ? i don't undretand the queston; half arc? amplitude? and how would you use kinetic/potential energy change to solve this porblem? i really...
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    Infinite 45 degree golden ratio thingy series related

    no no the distance traveled is divided by the square root of 2
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    Infinite 45 degree golden ratio thingy series related

    I've been trying to figure this problem out for hours on end and i can't even go on the tinernet to find the answer because its hard to search for. The problem is: You start off at hte coordinate (4,0). you move up 45 degrees and the distance traveled is now divided by the square root of 2...
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    Helicopter Problem: Calculating Lift Force on Rotors

    i cn't tell what I am getting wrong becuase its an online question where i plug in the values and get answers.. and thing is i keep getting values off by like. twenty or something. what i did is, fully: (13000)(9.8) + (900)(9.8) ------- (1) then i obtained (13909)(0.41) ------- (2) added the...
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    Helicopter Problem: Calculating Lift Force on Rotors

    There were two posts reltaed to this question but both of them are so contradictory; the question goes a 13,000kg helicopter accelerates upward at 0.41m/s^2 while lifting a 900kg car. to the nearest Newton what is the lift force exerted by the air on the rotors? now one post would be...
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    How far will you slide if you fall off a skateboard?

    the question is the topic, but I am sorri i don't have any numbers i can deal with, because we're just supposed to demonstrate that we understand how we solve htese porblems. unfortunately, I don't. could anyone just give me random numbers and tell me how to olve this question? thanks. I am...
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    Factors Affecting Friction: Experiment & Analysis

    i've just been given an assigment that's related to friction and what factors affect it. The basic stuff I've managed to understand is: 1. factors that affect friction are the materials which the objects are made out of and the weight. so they're asking us to perform an experiment that...
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