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Glite Dictionary
preimage

preimage

1 9.9
All input values that a function sends to a particular set
  • noun
  • /ˈpriːˌɪmɪdʒ/
  • Specialized
: preimagen
  • So if we have an open subset of Y, it's preimage will be open in X.

So if we have an open subset of Y, it's preimage will be open in X.

Examples

  • When analyzing the function, we can determine the preimage of any given element in the range.

  • To find the preimage of a point, you must look at all the inputs that lead to that output.

  • It doesn't matter whether an upload is called "the same person" as its biological preimage; it only matters whether it's a good decision to make this change.

    Blog text (32)

  • In mathematics, the preimage of a set under a function includes all elements that map to that set.

Surface Forms

preimage singular
preimages plural

Morphology

preimage = image (semi-transparent) = pre + image

Formed by the productive prefix 'pre-' + 'image', but the technical mathematical meaning ('inverse image') is specialized and not directly inferable by a general learner.

Etymology

Preimage comes from pre- meaning 'before' and image meaning 'picture' or 'result', and you can see pre- in words like preview. A helpful way to remember it in math is that the preimage is what comes 'before' the image — the original values that give a certain result.