Need help with solving for t value and plugging back into equation?

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To find the position of an electron described by the equation x=16*te^-t when it momentarily stops, the derivative x' is calculated as x'=e^-t - t*e^-t. Setting the derivative to zero leads to the equation -te^-t = -e^-t, simplifying to t = 1. The discussion confirms that this value of t is correct for determining when the electron stops. The thread emphasizes the importance of correctly applying calculus to solve for the t value and subsequently plugging it back into the original equation.
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1. An electron moving along the x-axis has a position given by x=16*te^-t m, where t is in seconds. How far is the electron from the origin when it momentarily stops?


2. Homework Equations
uv=u'v+uv'


3. The Attempt at a Solution
x'=e^-t - t*e^-t
e^-t - t*e^-t = 0
-te^-t = -e^-t
t = 1?
 
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hi itsgabriella! welcome to pf! :smile:

(try using the X2 button just above the Reply box :wink:)
itsgabriella said:
x'=e^-t - t*e^-t
e^-t - t*e^-t = 0
-te^-t = -e^-t
t = 1?

yup! :smile:

what's worrying you about that? :confused:
 
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