Let and . A relation from to is defined by S= (x,x^2):x X (1,3) . Which of the…

MATHEMATICS · Single correct · A Level · Mathematics · Algebra and Functions · Algebra and Functions

Problem

Let

X=\{-1,0,1,2\}

and

Y=\{0,1,2,3,4\}

. A relation

S

from

X

Y

is defined by

S=\{(x,x^2):x\in X\}\cup\{(1,3)\}.

Which of the following is true about

S

? (a) S is a function because each element of

X

is associated with some element of

Y

. (b) S is not a function because the input

1

corresponds to both

1

and

3

. (c) S is not a function because

(1,3)

is not of the form

(x,x^2)

. (d) S is not a function because

(-1,1)

and

(1,1)

share the same output

1