Given A={a,b,c,d} and B={c,d,e,f,g} .
R1={(a,c),(b,d),(c,e)},R2={(a,c),(a,g),(b,d),(c,e),(d,f)},R3={(a,c),(b,d),(c,e),(d,f)}
A relation is a function when every element of set A has image in B and a element of set A can-not have more than one image in set B.
So, Relation R3 is a function.
(c) Given f is a real valued function defined by f(x)=x2−9 .
(I) Function is defined for all real values of x. Hence,
Domain off=R
(ii) Now, as x2≥0⟹x2−9≥−9
Hence, Range of f=[−9,∞)
(iii) Representation of f as a set of ordered pair = {(x,x2−9):x∈R}
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