Need help with Proper integral of a uniformly charged rod

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Homework Statement



A uniformly charged rod is places along the x-axis from x=0 to x= L. carefully set up, but do not solve the proper integral to determine the x component of the electric field at the point (L,a)

Homework Equations


E=u<br /> \int \frac{dq}{(r^2)}<br />

for a line dq=λdl

The Attempt at a Solution


i know for a line dq=λdl
i think its something along the lines of
Ey=Kλy=<br /> \int \frac{dx}{(x^2y^2)^(3/2)}<br /> from 0 to L

I have no idea if this is right. I am using my notes to guide me.
 
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Coulomb's law for a linear charge distribution is:

\textbf{E}(\textbf{r})=\frac{1}{4\pi\epsilon_0}\int \lambda(\textbf{r}&#039;)\frac{\textbf{r}-\textbf{r}&#039;}{|\textbf{r}-\textbf{r}&#039;|^3}dl&#039;

Where dl&#039; is an infinitesimal length of the source, located at \textbf{r}&#039;, and the integration is over the entire line of charge.

Use \textbf{r}=x\mathbf{\hat{x}}+y\mathbf{\hat{y}}+z\mathbf{\hat{z}} and \textbf{r}&#039;=x&#039;\mathbf{\hat{x}}+y&#039;\mathbf{\hat{y}}+z&#039;\mathbf{\hat{z}} to find the x-component.
 
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