Hey There,

My question involves the u-substitution rule for calculus. I do not understand it intuitively, and am relying purely on a mechanical recital, so I do not understand what happens to the "du"?

here is an example of my confusion:

dx

= du

= (x^2)/2 + C

so I set and .

But where does the "du" go? It always seems to disappear, but I am not good enough at mathematics to understand why.

Thanks for your input.

-Warren