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Doing my final review for the semester and just want to make sure I have all my bases covered. (I'll more than likely have another 4-5 question to come today, but I'll start here).

Looking for someone to confirm whether this is the correct answer or not. If not, can you explain where I've gone wrong.

Find the equation of the tangent line to $y = 2xe^{-x}$ at the point (0,0)

1 (find derivative) :

$$ y' = 2(e^{-x}) + 2x(-e^{-x}) $$

2 (plug in x) :

$$ 2(e^{-0}) + 2(0)*(-e^{-0}) = 2(1) + 2(0)*(-1) $$

3 (plug that in to point slope formula) :

$$ y - 0 = 2(x + 0) --> y = 2x $$

Is this the correct answer?

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1  
Yes, indeed it is. –  David Mitra Dec 12 '12 at 16:57
    
@DavidMitra Thank you for the confirmation. Feels nice to know I'm on the right track for the final! Hope you stick around as I'll have some more questions shortly. –  StrugglingWithMath Dec 12 '12 at 16:58

1 Answer 1

Looks good to me. (30 characters? Bah.)

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There should be a link icon above the editing window that will aid you. –  David Mitra Dec 12 '12 at 17:02
    
Thanks, that helped. –  user108903 Dec 12 '12 at 17:08

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