write all the possible relations from A={1,2} to B={0}

**Given,** *A* = {1,2} and *B* = {0}.

We know that, if *A* and *B* be two sets, then a relation *R* from *A* to *B* is a subset of *A* × *B*.

Now, *A* × *B = *{(1,0), (2,0)}

Again, we know that total number of relations from *A* to *B* is 2* ^{mn}* where

*m*and

*n*are the number of elements of two non-empty finite sets

*A*and

*B*respectively.

Here, *m* = 2 and *n* = 1

So, number of relations from A to B = 2* ^{mn}* = 2

*= 4*

^{2×1}
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