Not sure, so maybe someone who knows can tell me.

Following on from the last blog, can we show ?

Assume a constant, exists such that , could give us this ?

**Edit**: Professor Rubin (see comments) tells me that, as I feared, what follows is not supportable:

Now, and this is the bit I have most doubts over, as and then and and assuming then we are left with .

Hence and therefore , the constant we are seeking.

But there are a lot of assumptions in there: anybody able to tell me how valid they are?

## 2 responses to “Good maths or bad maths?”

The bit about delta/n going to 1 is not supportable. Replace delta with n^2 (which approaches zero when n does) and your argument proves that n approaches 1 as n approaches 0 (immediately curing the Greek debt crisis, among other things).

Interchanging the order of limits is also tricky business. For any positive y, the limit of x/y as x approaches 0 from above is 0; so the limit of that limit as y approaches 0 from above is 0. Swap the order of the limits, treat the limit as y approaches 0 of x/y as infinity for positive x, and you get infinity for the outer limit.

[…] Post navigation ← Previous […]