>Is there something special about h?
No.
>Why not y or z instead?
It is convention. Just like functions are often called f and vector spaces V.

>>7691423
>How come derivatives always use h as the variable

Fermat used "e"
Descartes use tangent circles to find the normal
Leibniz used dx and dy
Newton used "o" and fluxions

>>7691423
On the picture... why does an investor think he can make money off a derivative?

>>7691426
>vector spaces V
What? They're not called E or F?

>>7692763
Same reason banks thinks they can make money off of mortgages.

>>7692797
But mortgages have interest, which means that people pay more to pay off the mortgage than the mortgage was worth.

Wait... the investor plain and simply get the mortgages?

That's fucking cool... I find it weird that a bank can sell a contract between a client and the bank.

f(x) = y and z is used when you get to the 3rd dimension. So y and z are already taken. And this format of limit makes x awkward to use. So they use something else, by convention, y.

I prefer
[math]\lim{x\to a} \frac{f(x) - f(a)}{x - a}[/math] myself for this reason.

>>7691423
I learned it like this. [math]\frac{{df}}{{dx}} = \mathop {\lim }\limits_{\Delta x \to 0} \frac{{f\left( {x + \Delta x} \right) - f\left( x \right)}}{{\Delta x}}[/math]

convention

i was at dinner the other night and someone tried debating me about what "g" meant in "math". don't be fooled.

>>7692805
>That's fucking cool
Not when there's simultaneously a housing bubble going on.
https://en.wikipedia.org/wiki/Financial_crisis_of_2007%E2%80%9308

>>7692815
g is to f as luigi is to mario

>>7692805
In order to make the system work only a select few can purchase such instruments. The restrictions are put in place to keep people from indirectly buying their own debt and destabilizing the system.

>>7692789
Usually the bases of the vector spaces, often denoted with V, W, are called E, F.

>>7692841
Never has a truer thing been said.