Solution : Let ’ s draw arrow diagram . We can see that for every element of set A , it has only 1 image / output in set B . Thus it is a function .
Real & Real Valued functions
Real Value function : Range à R or subset of R ( that is output is R but not input )
Real function : Both range & domain à R or subset of R
Graph of identity function , f ( x ) = x , is a straight line . Domain = R & Range = R .