Recent content by emptymaximum

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    Solving Integration by Parts: Stuck on \int \sqrt{9-x^2}dx

    9 - x² is a difference of squares; 9 - x² = (3-x)(3+x) = f(x)g(x) then: √(9 - x²) = √[(3-x)(3+x)] = √(3-x)√(3+x)
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    Moment of inertia / torque question

    ummm. i think you mean to say it is attached to a solid 'brick' \vec{\tau} = \vec{r} \times \vec{F} where \vec{r} is the position vector from the axis of rotation to where the force is acting, and \vec{F} is the force. the direction of the vector produced by the cross product is given...
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    Nevilles Method for approximation

    UPDATE: i figured out how to make the table by interpolating tables given. thanks anyways.
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    Solving Integration by Parts: Stuck on \int \sqrt{9-x^2}dx

    why do you need to get them out? you can represent (9-x²) as a product of two functions of x easily. If f(x) is a second degree polynomial, then f(x) = g(x)h(x) by definition. hint: try factoring f(x)
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    Solving Integration by Parts: Stuck on \int \sqrt{9-x^2}dx

    no, you can't use dx = dv. that isn't going to help you out, because you'll need to integrate x in the next step and the more steps you have, the more you integrate x and you can do that forever. why? in order to use integration by parts, the integrand needs to be a product of two functions of...
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    Solving Integration by Parts: Stuck on \int \sqrt{9-x^2}dx

    the thing to remember about integration by parts is that in the first integral you need to have a PRODUCT of two functions. \int u dv = u v - \int v du so the real question is, how do you make \sqrt{9 - x^2} be a product of two terms?
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    Nevilles Method for approximation

    basically, i don't get it at all. i understand that x0 P0 P01 x1 P1 P012 P12 x2 P2 let's approximate f(x) where x is some number. i have some Pi given and a Pi(i+1) and Pi(i+1)(i+2) i also have the xi i don't know what f(x) is, some...
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    Only for genius people: jumping stilts on a trampoline.

    so then now you agree with the above statement?
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    Solving Trigonometric Equations

    you can divide through even if it has the posibility of being = to zero. the reason for this is because trig functions are FUNCTIONS. when you take calculus you'll see that you can examin how a function behaves close to zero. as φ -> 0 for sinφ/sinφ , that ratio actually -> 1. when it is = 0...
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    Solving a Tricky Natural Log Question

    you put it in your calculator wrong?
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    Only for genius people: jumping stilts on a trampoline.

    m \ddot{x} = -m g + b x - k x where +ve x is upward, b is the spring constant of the trampoline, and k is the spring constant of the stilts.
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    Only for genius people: jumping stilts on a trampoline.

    the original post said nothing about formulas. if you want a formula, it would be the formula for a damped harmonic oscillator, with the restoring force of the stilts being the damping force. also, it is a good idea to have an understanding of what is going on when you have a formula so's you...
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    Only for genius people: jumping stilts on a trampoline.

    how the springs work is completely irrelevent. pneumatic, hydraulic, rubber bands, whatever. it's what they do that's important, and what they do is damp the upward motion of the trampoline. he'll go less high wearing the things, BECAUSE the damper takes more energy than it gives back. the...
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    Faraday's Induced Emf: Help & Solutions Needed

    the radius is .2m, not .10 .10 is what you wrote for seconds. the area of a circle is ╥r^2 a loop would be one turn a coil would be multiple turns
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