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

If a tank holds 5,000 gallons of water which drains from the bottom of the tank

in 40 minutes, then Torricelli's Law gives the volume V of water reminaing in the

tank after t minutes as

V = 5000(1 - t / 40)^{2}, 0 <= t <= 40. The rate at which water is

draining from the tank after 10 minutes, in gal/min, is

2. Relevant equations

3. The attempt at a solution

I figure I'll just find f'(t).

[5000 lim_{h-> 0}(1 - (t+h)/40)^{2}] - [5000 lim_{h->0}(1 - t/40)^{2}]

But now I'm stuck. I believe I have to use the power rule but don't see how to implement it.

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# Homework Help: Calc I Question

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