Question

Which set of ordered pairs in the form of (x, y) does not represent a function of x?

A. {(1, 1.5), (2, 1.5), (3, 1.5), (4, 1.5)}

B. {(0, 1.5), (3, 2.5), (1, 3.3), (1, 4.5)}

C. {(1, 1.5), (–1, 1.5), (2, 2.5), (–2, 2.5)}

D. {(1, 1.5), (–1, –1.5), (2, 2.5), (–2, 2.5)}

Answer 1

Option B

Explanation:

For answering this question we must understand what is a function.

A function is different from mapping.

Mapping is just a subset of AxB where A and B are two sets.

But function is constrained to the point that elements of I set will have unique image in second set.

We find From the options

But in option B,, we find that 1 has two images 3.3 and 4.5. i.e. 1 does not have unique image. Hence not a function.

All other options the first element in ordered pair have a unique image.

Hence all other options are functions.

Only option B is not a function.