Quote: "Chris, I know its subscript but I wouldn't personally use i at all, I mean we have r (yet that could get mixed up with product moment and spearmans) and 22 other letters we could possibly use whats the point of using i?"
It's because i, j and k are always used as the components or coordinates of something. In the summation convention, you're generally summing components, or different products of components or something so it makes absolute sense to use i.
@ Everyone
0/0 is not zero, and not 1. It's undefined, that is the end of the discussion, stop trying to produce "proofs" to calculate it.
What's more interesting is limits of fractions where the top and bottom both go to zero.
For example, when x is zero, sin( x ) is zero, and cos( x ) = 1, or 1 - cos( x ) is zero.
But if we think about the fractions
sin( x ) / x and
( 1 - cos( x ) ) / x, and then make x smaller and smaller, they both tend (in a way) to "0/0" but they actually go to different values, sinx/x goes to 1 and 1 - cosx/x goes to 0.
The proofs of that are not hard to understand.
(by the way you shouldn't use a Taylor Series or L'Hopital's Rule to work out those fractions because you actually need to know what they come to to prove that the derivative of sinx is cosx)
-= Out here in the fields, I fight for my meals =-
