From what I was reading, the apparent definition goes as: The Identity Function on E is the function I(adsbygoogle = window.adsbygoogle || []).push({}); _{E}from E into E defined by I_{E}(x) = x. Since I_{E}is the set of all ordered pairs (x,x) such that x ϵ E, I_{E}is also called the diagonal subset of E x E.

If f is a function from E into F, clearly

1. f o I_{E}= f,

2. I_{F}o f = f, in which o is a composition operation

I understood 1., but I'm stuck on understanding on how 2. works. The definition is also confusing me; by how I read it, the identity function is the original function operating on itself...which, as stated, confuses me...any clarifications?

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# Identity Functions

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