Math
posted by Dave .
Evaluate the integral of e^(1/x) / x^2 from [1,2].
I let u =1/x, but then I am stuck because I am not sure what is the derivative of 1/x is?
The answer in the book is e sqrt(e)

Math 
Steve
let u=1/x
du = 1/x^2 dx
∫e^(1/x)/x^2 dx
= ∫e^u du
= e^u = e^(1/x) [1,2]
= e^(1/2) + e^(1/1)
...
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