Question

Check whether functions in the following diagrams are onto :

Answer 1

(i) Since, every element in B has pre-image in A, so f₁ is onto function.

(ii) Since, element in B has pre-image of A. So f₂ is onto function. 

(iii) Since 3 ∈ B does not have pre-image A. So f₃ is not onto function.

(iv) Since, 6 ∈ B does not have pre-image of A. So f₄ is not onto function.