Help Solving High School Math Integration Problem

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i've been having trouble solving this one for high school math:

it's under the substitution section


integrate:

[e^(x^0.5) ] / (x^0.5)

do you guys think you can help me with this one?

thanks
 
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mathmathmath said:
i've been having trouble solving this one for high school math:

it's under the substitution section
Have you tried a substitution?? There are only a couple of choices to choose from, and one is really obvious.

And the LaTex for this equation is

[tex]\int \frac{e^{x^{\frac{1}{2}}}}{x^{\frac{1}{2}}}dx[/tex]

you can click on the equation to see the LaTex code.
 
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Actually, once you have more experience integrating exponential functions, you will realize a substitution is not really necessary.
 
i'm still lost, and this is supposed to be a routine question :(

i think there is a property of e that i am not familiar with that might be holding me back. any hints?

i've looked at two ways, neither of which seem to be any good.

1. tried substituting u for x^.5, which seemed to do no good as it didnt offer a du/dx.
2. tried substiuting u for e^x^.5, using the idea that ln u = x^.5 for the denominator. again, this didn't offer me much help.

the answer for this one is 2e^x^.5, and working backwards didn't seem to give me any more ideas. sorry if I'm missing something blatant :(
 
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To solve the problem via substitution, what substitution should you try?

To solve it in a more direct manner, try differentiating the numerator. What do you realize?
 
Let [tex]u=x^\frac{1}{2}[/tex],
so [tex]x=u^2 ;dx=2udu[/tex]
substitutes them into your integral, it become:
[tex]\int \frac{e^u}{u}2udu[/tex]
 
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ah. :( after all the fuss about that root of x... thanks very much for all the help