Effortlessly Integrate \frac{2mdx}{cx^2} from x to 0 | Expert Tips

AI Thread Summary
The discussion centers on the integration of the function 2mdx/cx^2 from x to 0, highlighting the issue of using the same variable in both the limits and the integrand. It suggests rewriting the integral as 2mdt/ct^2 to avoid confusion. However, this leads to a further complication, as the integral becomes improper due to the behavior at the lower limit of 0. Ultimately, the integral does not exist because of these issues. Proper variable distinction and understanding of improper integrals are crucial in this context.
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i need to intergrate this function
\frac{2mdx}{cx^2}
from x to 0
 
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If you meant to write:
\int_x^{0} \frac{2m}{cx^2}dx
Then you've got the variable of integration in the limits of integration which is ...problematic.
 
It is bad practice, although it is often done, to use the same letter to represent the "dummy" variable of integration and as a variable outside the integral (as in one of the limits of integration).

If you meant
\int_x^0\frac{2mdt}{ct^2}

Then rewrite the t2 in the denominator as t-2:
\frac{2m}{c}\int_x^0t^{-2}dt

You still have a problem- that's an improper integral which will have serious difficulties at 0! This integral does not exist.
 
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