Question

7. Let f = { (2, 7), (3, 4), (7, 9), (–1, 6), (0, 2), (5, 3) } be a function from
A = { –1, 0, 2, 3, 5, 7 } to B = { 2, 3, 4, 6, 7, 9 }. Is this (i) an one-one function
(ii) an onto function (iii) both one-one and onto function?

Answer 1

1. The given function f is one - one
because different elements in A has different images in B.


2. Since Range = co domain , the function f is onto.
In otherworlds each element of B has preimage in A under f.

3. Clearly f is both one one and onto

I hope this answer helps you

Answer 2

It is given that ,

f = { (2,7),(3,4),(7,9),(-1,6),(0,2),(5,3) }

A = { -1 , 0, 2 , 3 , 5 , 7 }

B = { 2 , 3 , 4 , 6 , 7 , 9 }

Therefore ,

f is a Bijective Function .

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If the function ' f ' is both

one - 0ne and onto then it

is called a Bijective Function .

• If f is a Bijective then n(A) = n(B)

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