Aftab hassan
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- May 16, 2019
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Define domain and range?
As an 'old-timer' I will tell you the everything about those two concepts depends upon your particular text-material.Define domain and range?
I uploaded the image above please describe it.As an 'old-timer' I will tell you the everything about those two concepts depends upon your particular text-material.
Here is the way I write about it:
The statement that \(\displaystyle f: A\to B\) means that
1) \(\displaystyle f\subset A\times B\)
2) \(\displaystyle (\forall x\in A)(\exists y\in B)[(x,y)\in f]\)
3) No two pairs in \(\displaystyle f\) has the same first term.
We write that if \(\displaystyle (a,b)\in f\) then \(\displaystyle f(a)=b\).
The domain of \(\displaystyle f\) is \(\displaystyle A\) and the final set(range/codomain) is the set of second terms of \(\displaystyle f\).