Integration of (e[SUP]-√x[/SUP])/√x

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The integral of (e-√x)/√x was initially approached with incorrect limits, changing infinity to negative infinity. The correct substitution is √x, leading to the proper evaluation of the integral. After correcting the limits and substitution, the final answer was determined to be 2/e. The discussion highlights the importance of using the positive root in integration problems. Understanding the limits and substitutions is crucial for accurate calculations in calculus.
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Homework Statement
Compute the integral with upper bound infinity and lower bound 1
Relevant Equations
Integral of (e[SUP]-√x[/SUP])/√x
(e-√x)/√x (integral from title)

I integrated by substituting and the bounds changed with inf changing to -inf and 1 changing to -1

My final integrated answer is -2lim[e-√x]. What happens to this equation at -inf and -1? As I can't put them into the roots
 
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I'm not sure I understand the difficulty.
 
Anne5632 said:
Homework Statement:: Compute the integral with upper bound infinity and lower bound 1
Relevant Equations:: Integral of (e-√x)/√x

(e-√x)/√x (integral from title)

I integrated by substituting and the bounds changed with inf changing to -inf and 1 changing to -1

My final integrated answer is -2lim[e-√x]. What happens to this equation at -inf and -1? As I can't put them into the roots
You have the wrong limits. \sqrt{x} is the positive root. Thus \sqrt{1} = 1 and \sqrt{+\infty} = +\infty.
 
pasmith said:
You have the wrong limits. \sqrt{x} is the positive root. Thus \sqrt{1} = 1 and \sqrt{+\infty} = +\infty.
Thank you, I originally let my substitution = -√x
But √x is better
Final answer now is 2/e
 
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