(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Given that Q=Pa^t and Q doubles between t and t+d, prove that d is the same for all t.

2. Relevant equations

Q=pa^t

3. The attempt at a solution

This is what I've tried so far:

[tex]Q_0=Pa^t[/tex] and [tex]Q_1=Pa^{t+d}[/tex]

Then:

[tex]\frac{a^{t+d}}{a^t}} \equiv 2[/tex]

This is where I begin drawing blanks again. I want to say take the log, but I'm not sure if that is right.

If so, doesn't this give me:

[tex]\frac{t+d}{t} \equiv log(2)[/tex] ?

Then from there: [tex]d \equiv log(2^t)-t[/tex]

Would that be correct?

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# Homework Help: Proving the constant rate of doubling for an exponential function

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