Question

Let A = R − {3} and B = R − {1}. Consider the function f: A → B defined by

. Is f one-one and onto? Justify your answer.

Answer 1

A = R − {3}, B = R − {1}

f: A → B is defined as.

.

∴ f is one-one.

Let y ∈B = R − {1}. Then, y ≠ 1.

The function f is onto if there exists x ∈A such that f(x) = y.

Now,

Thus, for any y ∈ B, there existssuch that

Hence, function f is one-one and onto.