Re: Lens Algebra

On Tue, 24 Oct 2006 vreddyp@xxxxxxxxx wrote:
William Elliot wrote:

It's terrible. You haven't explained anything, not a(x), c(p_x) nor F.
Worse than that, b isn't even mentioned. Don't you worry about you
discouraging your thought process. You have so little to discourage.

Man, how unkind are you. Do you scare your students (if you are a
teacher) like this?

Good riddance to those who don't want to work.

Ok, here we go again:

"a" is the name of a function that maps or relates two variables x and
y such that x.y = 1.

Gibberish.

Let me write it as
y = a(x) if x.y = 1

What's the domain and codomain of a,b and c?

Using similar notation I define b and c as follows.
y = b(x) if x+y = 1
y = c(x) if x+y = x.y

a:R -> R, x -> 1/x
b:R -> R, x -> 1 - x

c:R -> R, oh bull.
x + y = xy
y = x/(x - 1)
c:R -> R, x -> x/(x - 1)

You better fix the domains for a and c.

f:X -> Y, x -> expression of x
is the function from X into Y that maps x to the 'expression of x'.

R is the real numbers. Convention uses f,g,h for functions and
a,b,c for constants, just in case you want to appear proficient.
.