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@jim_thompson5910 @iambatman
Find the first few derivatives and observe a pattern to find nth derivative of g
I think I would write as a product for fun \[g(x)=xe^{-x}\] then differentiate
1st:e^-x-xe^-x 2nd:e^-x-2xe^-x 3rd:3e^-x-xe^-x
it has something to do with -1(x-n) right?
with an exponent
\[g^{(1)}(x)=1e^{-x}-xe^{-x} \\ g^{(2)}(x)=-2e^{-x}+xe^{-x}=(-1)(2e^{-x}-xe^{-x}) \\ g^{(3)}(x)=3e^{-x}-xe^{-x}\]
Do you notice it is alternating
also the part in front of e^{-x} is the number of the n-th derivative
like what i mean is : the 1st derivative we have a 1 in front of e^{-x} the 2nd derivative we have a 2 in front of e^{-x} and so on...
so its e^(-nx)?
nothing is changing in the exponent area
ok
by the pattern above i can say the 4th derivative would be \[g^{(4)}=(-1)(4e^{-x}-xe^{-x})\]
the 5-th derivative would be \[g^{(5)}=5e^{-x}-xe^{-x}\]
so can you take a guess at what the n-th derivative would look like
not yet. it has something to do with even and odd functions though
\[g^{(1)}(x)=(-1)^{1+1}(1e^{-x}-xe^{-x}) \\ g^{(2)}(x)=(-1)^{2+1}(2e^{-x}-xe^{-x}) \\ g^{(3)}(x)=(-1)^{3+1}(3e^{-x}-xe^{-x}) \\ g^{(4)}(x)=(-1)^{4+1}(4e^{-x}-xe^{-x})\]
g^(n)(x)=(-1)^(n+1)(e^(-x)-xe^(-x))
what about the number in front of e^(-x)?
ne^(-x)
ok
thank you so much
\[g^{(n)}(x)=(-1)^{n+1}(n e^{-x}-xe^{-x})\]
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