Position of an Electron Moving on the X-Axis: Solve for t

[mb85]

A electron moving along the x-axis has a position given by
x = 10te^-1.9t m, where t is in seconds. How far is the electron from the origin when it momentarily stops?

i not exactly sure how to solve for t, since it has 2 t variables in the problem. any help would be appreciated.

 

[eep]

Google for the product rule.

 

[vaishakh]

d(e^x)/dx = e^x.
I think this is where you are stuck.