Because x in the equivalent infinitesimal can be replaced by any formula, as long as it tends to zero, it can be replaced equivalently.

For example, x~sinx tends to zero equivalent, and x- 1 ~sin(x- 1) tends to 1 equivalent.

X- 1 approaches 0, and x approaches 1. As long as they are found to be equivalent when approaching a certain number, formulas can be used.

Noun explanation:

Aristotle (384-322 BC), an ancient Greek philosopher, believed that infinity could exist, because finite quantities were infinitely separable, but infinity could not be achieved.

/kloc-in the 20th century, a great Indian mathematician, Bascara, appeared, and his concept was close to that of theory.

Mobius belt is usually regarded as the creative source of the infinite symbol "∞", because if someone stands on the surface of a huge Mobius belt and walks along the "road" he can see, he will never stop. But this is an untrue rumor, because "∞" was invented before Mobius belt.