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    Does the following function have an extremum? If yes, find it. Is it a maximum or minimum?

    f(x) = xe^-x

    I was thinking of using the product rule to differentiate but i don't know where to go from there
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    (Original post by chandmeister)
    Does the following function have an extremum? If yes, find it. Is it a maximum or minimum?

    f(x) = xe^-x

    I was thinking of using the product rule to differentiate but i don't know where to go from there
    When you differentiate, what do you get? Set the expression you get equal to 0 and solve for x from there. You're thinking along the right lines.
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    (Original post by Zacken)
    When you differentiate, what do you get? Set the expression you get equal to 0 and solve for x from there. You're thinking along the right lines.
    When I differentiated I got e^-x -xe^-x. I then equated it to zero and took a common factor of e^-x out to get this:

    e^-x (1-x) = 0

    then i got that x=1 and f(1) = 1/e so the extremum i believe is (1,1/e)

    The other bit is pretty self explanatory at this point. Thanks for your help!
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    (Original post by chandmeister)
    When I differentiated I got e^-x -xe^-x. I then equated it to zero and took a common factor of e^-x out to get this:

    e^-x (1-x) = 0

    then i got that x=1 and f(1) = 1/e so the extremum i believe is (1,1/e)

    The other bit is pretty self explanatory at this point. Thanks for your help!
    Perfect.
 
 
 
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