Valhalla Legends Archive

Member Forums => Yoni's Math Forum => Topic started by: 111787 on March 15, 2006, 08:38 PM

Title: little math help(notation and what not)
Post by: 111787 on March 15, 2006, 08:38 PM
ok so i want to write this all mathematically right.

The number of integers in the range of the function f(x)=y where x and y are both elements of the set {0,n} greater than or equal to z.
Title: Re: little math help(notation and what not)
Post by: Rule on March 15, 2006, 09:25 PM
Quote from: 111787 on March 15, 2006, 08:38 PM
ok so i want to write this all mathematically right.

The number of integers in the range of the function f(x)=y where x and y are both elements of the set {0,n} greater than or equal to z.

This sort of "new math" is my Achilles' heel (probably because it sucks and I haven't studied it).  What class is this for?

I think you need to word your question a little more carefully.  Do you want
all integers the meet the conditions you described, or the cardinality of the
set of all integers that meet the conditions you described? Also, is z a real
number, an integer, ...?  Keep in mind a set cannot be greater than or equal to z (would be clearer to say x and y are greater than equal z and belong to some set {0, n}  (n is some unspecified integer???).

Here is a "guess" making some assumptions based on what you've said. 
You can change it to fit what you want.   I also am not sure of a symbol that
means "cardinality of this set."  I think the word "dim" might work (e.g. dimension of the set).

Cardinality of this set (note Z represents the set of all integers and
the upside down v means logical AND):

dim (http://www.valhallalegends.com/rule/mathhelp.jpg).

I apologize in advance for not using LaTeX :'(



Modification:  You may also want to add: for all integral (h, j) such that h=f(j),
h AND j are elements of {0, ..., n} AND (h AND j) >= z