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#1 2006-08-22 21:50:30

Titus
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Derivatives

I can't work out the derivative for this equation;

P = 2t/3 + t - 40t - 5

and then i need to find what 't' is when the derivative of the above equation = 0.

Any help would be great.
Thanks!

#2 2006-08-23 00:28:23

numen
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Re: Derivatives

Generally speaking,



The left side is your derivative. Does this help or should I give you some hints?
When you've got the derivative, set it equal to 0 to obtain your equation, then solve for t.


Bang postponed. Not big enough. Reboot.

#3 2006-08-23 06:07:46

luca-deltodesco
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Re: Derivatives

and ofcourse
if f(x) = a0(x) + a1(x) ... an(x);
f'(x) = a0'(x) + a1'(x) .... an'(x);

so

P(t) = 2t/3 + t - 40t - 5
P'(t) = 2t + 2t - 40 = 0, 2(t+) = 40, (t+)^2 = 20, t = - √(20) = - 4, t = 4, t = -5

Last edited by luca-deltodesco (2006-08-23 06:08:39)


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