Solving for k1 and k2 in a Simple Electrical Engineering Question

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To solve for k1 and k2 in the equation q(t) = (k1)t^2 + (k2)t, the relationship between current and charge must be utilized, specifically i(t) = dq/dt. By differentiating the charge equation, the current can be expressed as i(t) = 2(k1)t + k2. Given the initial conditions i(0) = -5 A and i(1) = +5 A, these can be used to set up a system of equations to solve for k1 and k2. The discussion highlights that this type of problem-solving is also relevant in differential equations and Fourier series. Understanding these concepts will facilitate future learning in electrical engineering.
wk1989
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Hi, I'm doing an introductory electrical engineering course on my own and so far have gotten a few pages into the book. I understand pretty much all the problems so far except for this one.
"The charge entering a terminal of an element is given by the equation
Code:
q(t) = (k1)t^2+(k2)t
Where 1 and 2 are subscripts.
If i(0) = -5 A and i(1)=+5A, find k1 and k2."

I think you have to use the integral of i(t) which gives q(t) but I'm not sure how to start. Any help would be appreciated.
 
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Not the integral of i(t), instead start with this basic equation:

i = \frac{dq}{dt}
 
thanks!
 
Just a note to the OP, such type of solving for constants can be seen in solving particular solutions for differential equations and Fourier series (if you take it a step ahead.) Just something to remember, so that when you actually see it later on, it'll be a piece of cake.
 
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