What is function ?

Explanation

What is a Function?

If every element of a non-void set X has a single image or range to a non-void set Y in a relation ‘f’, then relation ‘f’ is called a function.

Or

If ‘f’ is a function from set X to set Y and (x,y) ∊ f, then f(x) = y, where a has an image as b, under function f and b has a preimage as a, under ‘f’. It is denoted as;

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