1. ## Integration problem

Hi im not sure how to do this problem:

$\displaystyle \int \frac{1}{10}te^{0.1t} dt$

Thanks

2. Originally Posted by anothernewbie
Hi im not sure how to do this problem:

$\displaystyle \int \frac{1}{10}te^{0.1t} dt$

Thanks
Do you know integration by parts?

3. Read this Integration by parts - Wikipedia, the free encyclopedia

For $\displaystyle \int uv' = uv - \int vu'$

In your case make $\displaystyle u=\frac{1}{10}t$ and $\displaystyle v' = e^{0.1t}$

now find $\displaystyle u'$ and $\displaystyle v$

4. Right finally found time to get back to this problem, this is where im at.

$\displaystyle \int \frac{1}{10}te^{0.1t} dt$

Make $\displaystyle v = \frac{1}{10}t$

So $\displaystyle \frac{dv}{dx} = \frac{1}{10}$

And Make$\displaystyle \frac{du}{dx} = e^{0.1t}$

So $\displaystyle u = 10e^{0.1t}$

Using

$\displaystyle \int uv' = uv - \int vu'$

I get:

$\displaystyle \int \frac{1}{10}t \times e^{0.1t} = 10e^{0.1t} \times \frac{1}{10}t - \int 10e^{0.1t} \times \frac{1}{10}$

Am I doing this right or am i on totally the wrong track?

God I suck at maths

5. Originally Posted by anothernewbie

$\displaystyle \int uv' = uv - \int vu'$

I get:

$\displaystyle \int \frac{1}{10}t \times e^{0.1t} = 10e^{0.1t} \times \frac{1}{10}t - \int 10e^{0.1t} \times \frac{1}{10}$

Am I doing this right or am i on totally the wrong track?

You are doing great, now integrate on the RHS on you are done.

Originally Posted by anothernewbie

God I suck at maths
Not this time you didn't, well done!

6. Originally Posted by pickslides
You are doing great, now integrate on the RHS on you are done.

Not this time you didn't, well done!

Woop, thanks will give the rest a go later on today.

Thanks