Question

Which of the following is not a function: R = {(1,-1), (2,-1), (3,-1)} R = {(1,2), (2,3), (3,4) (4,1)} R = {(1,-1), (-1,2), (1,3)} R = {(1,1), (2,4),(3,9),(4,16)}

Answer 1

Answer:

please mark the brainlist I am a following you a mark the brainlist.