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MonDie

The "Introduction to Calculus" tutorial is misleading in that you assume the other lessons will go deeper than the intro. I need to learn integrals to understand some problems pertaining to "time derivatives" (d_/dt).
Apr 19, 2017
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    MonDie
    I learned that the time derivative is the derivative function of a function with time as its x-axis, but now I need to know what it means when the top is unspecified: d/dt (rather than di/dt or dv/dt).
    Apr 24, 2017
  • MonDie's Photo
    MonDie
    More broadly, I need to know how to simplify equations with derivatives or integrals. This is not straightforward since the integral has all this extra crap. For example, an inductor's instantaneous voltage is v=L(di/dt), but the equation rearranges to i=(1/L)(integral(v dt + k1)). I understand that you can remove constants from the integral (1/L), but what is with the dt + k1?
    Apr 24, 2017
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    MonDie
    I also need to understand how the integral can change from a time integral (t1-t2) to a current integral (i1-i2) by multiplying the dt with a spare di/dt. I am even more dumbfounded by the change L(di/dt)i=(d/dt)[(1/2)Li^2] and current-integral of Li di = (1/2)L[i22-i21] where L is the constant of Inductance.
    Yesterday, 03:18 PM