If f: A → B is an injection, such that range of f = {a}, determine the number of elements in A.

Asked by Sakshi | 1 year ago |  59

##### Solution :-

Given f: A → B is an injection

And also given that range of f = {a}

So, the number of images of  f = 1

Since, f  is an injection, there will be exactly one image for each element of f .

So, number of elements in A = 1.

Answered by Aaryan | 1 year ago

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