Question

Question about image (typing)

Answer 1

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Answer 2

In my notes image is shown as \[f(I)=\left\{ f(x):x \in I \right\}\] but shouldn't it be \[I=\left\{ x \in X:f(x) \in Y \right\}\] ?

Answer 3

In this case, \(Y\) is the co domain?

Answer 4

What matters is that the image is all the elements the function outputs. Some of the elements in the codomain might not be used, so we need to distinguish the two.

Answer 5

I figured it out. For some reason I had it stuck in my head that image was a subset of the domain when it's actually a subset of the range.

Answer 6

Range is an ambiguous term. For some people it means image and for others it means codomain.