wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

Let A = {−1, 0, 1} and f = {(x, x2) : x ∈ A}. Show that f : A → A is neither one-one nor onto.

Open in App
Solution

A = {−1, 0, 1} and f = {(x, x2) : x ∈ A}
Given, f(x) = x2

Injectivity:
f(1) = 12=1 and
f(-1)=(-1)2=1

1 and -1 have the same images.
So, f is not one-one.

Surjectivity:
Co-domain of f = {-1, 0, 1}

f(1) = 12 = 1,
f(-1) = (-1)2 = 1 and
f(0) = 0
Range of f = {0, 1}
So, both are not same.
Hence, f is not onto.

flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Theorems
MATHEMATICS
Watch in App
Join BYJU'S Learning Program
CrossIcon