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C4 differential equation question

I really shouldn't care about this. But, curiosity is a strong thing.

How do you solve this
dVdt=20kV\frac{dV}{dt}=20-kV where K is a positive integer.

It has to be in the form
V=A+BektV=A+Be^{-kt}
This is a strange question, I'm pretty sure you can't use separation of varibles to do it. Anyone?

P.S. I know abit of FP3, but I still can't solve it. The only thing I can think of is to multiply by t then play around with that.
You can use separation of variables :p:

Inverting both sides of the equation, thn integrating both sides wrt V you get:

t = integral of 1/(20 - kV) dV
Reply 2
tazarooni89
Inverting both sides of the equation, thn integrating both sides wrt V you get:

t = integral of 1/(20 - kV) dV

That works.

I don't know why I didn't think of that. I can't believe I'm that stupid.
try doing c4 before attempting c3

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