What exactly is “dx” in integrals and derivatives?

Question

I attended the Calculus course at my university, but neither I or my colleagues could understand what “exactly” is dx and its purpose. Thanks!

In: Mathematics

Answer 1

The “d” refers to the delta of x. But not just any delta; it’s only written as “d” when we’re talking about the delta as it approaches zero — or is infinitely small. So you can think of it as x at a single point along the function.