Another math question

[shams]

Guys,

Read up on the concept of "limits" (fundemental to how differential calculus & integration work).

Limit (SUM (9/10^x)) as x --> 1..infinity = 1 (*)

(i.e. 9/10 + 9/100 + 9/100 + ... = 1) 

Anything other than the limit is NOT 1 (1 > value). 

(* - a common way of describing this is using "." - repeater - its basically the same thing).

....

Since we are talking about funky maths, here is a cute on I "proved" many years back (it doesn't actually work, the question is why).

When you have two straight lines on a graph, that are perpendicular - the product of their gradients is ALWAYS -1, i.e.:

m1 x m2 = -1 (where m1, m2 are the gradients of each line, in the form y = mx + b)

Try applying this to the x/y axis of the graph!

Gradient x-axis = 0
Gradient y-axis = 1/0 (infinite)

Therefore, 0 x 1/0 = -1 (!!)

(or 1 = -1 !!)