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

Find a > 0 such that the tangent line to the graph of

f(x) = [itex]x^{2}[/itex]e[itex]^{-x}[/itex] at x = a passes through the origin.

2. Relevant equations

3. The attempt at a solution

First I found the derivative to be:

[itex]-e^{-x}(x-2)x[/itex]

, which is the slope of the function.

I know the tangent line must pass through the origin (0,0), but I'm a bit stuck.

I took a year off from math and am trying to get back in to math mode. Any help to lead me to the next step would be great.

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# Homework Help: Tangent line that passes through origin

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