What is the Significance of dx in Integrals?

[beauty-eyes]

What is dx mean in intagral?

 

[malawi_glenn]

that x is the variable that you perform the integral over. Variable of integration.

It comes from the definition of integral, that you sum over the function value multiplying it with a very very small x-intervall (length multiplied with height). Riemann summary. If we make the intervall infinitesimal (dx), the we have to do, in practice, an infinite amount of summations over these "function value" * "length of intervall"

http://en.wikipedia.org/wiki/Integral