Question

If f(x) is a function and f(1) = 5, then which of the following could not be true?
f(1) = 1
f(2) = 1
f(5) = 5

Answer 1

a

Answer 2

Hint

Since a function cannot have more than 1 output (y) per input (x) we know that each 'x' cannot have more than 1 'y'

So if we know f(1) = 5

This means that when x = 1...y = 5

If that is true...and for this to remain a function...that means when x = 1...we cannot have ANY other answer expect for 5

Which solution choice agrees with that?