What is theta in the remainder formula?

Question

Mathematics

en.wikipedia.org/wiki/%D0%FF%E4_%D2%E5%E9%EB%EE%F0%E0
What is theta between 0 and 1? What value to take then?

Answer 1

So the trick is that the remainder is an estimate of the accuracy of the approximation. If theta had a certain value, then you would expand the function into a finite sum without error.