Q11 of 107 Page 10

Let f: R → R be defined as f(x) = x4. Choose the correct answer.

f: R → R be defined as f(x) = x4.

Let x, y ϵ R such that f(x) = f(y)


⇒ x4 = y4


⇒ x = �y


Therefore, f(x1) = f(x2) which does not implies x1 = x2.


For instance, f(1) = f(-1) = 1


Therefore, f is not one-one.


Now, an element 2 in co-domain R.


We can see that there does not exist any x in domain R such that


f(x) = 2


Therefore, f is not onto.


Therefore, function f is neither one-one nor onto.

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