Question

Which of the following does not represent one-to-one function?

A. Gas has one function when put in a car.

B. A house belongs to one person.

C. A washing machine has one function (to wash)

D. An x-ray is associated with the one function of taking internal pictures.
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Answer 1

A house that belongs to one person (option B) does not represent a one-to-one function.

• One to one function is a relationship between two things in which one can only belong to another.

• It can be explained in the mathematical term that for input value "x" there is unique output "y". The vice versa should also be true. The ratio of 1:1 represents a one-to-one function.

Option A: Gas has the function of generating fuel inside the car.

Option C: The washing machine only has the function of washing clothes.

Option D: X-ray functions to take internal pictures of the body in radiology.

They are all one-to-one functions.

Option B: House belongs to one person is not one-to-one function because:

• House can belong to more than one member or it belongs to one family.

• House is not a function. It shows the relationship of a person with the house. One-to-many relations are not function.

Answer 2

The correct answer is option (b).

• A one-to one function is a function of which the answer is unique i.e it will never repeat.

• A house belongs to one person doesn't represent one-to-one function because:
• A House can belong to more than one member or it belongs to one family.
• A House is not a function as it shows the relationship of a person with the house. One-to-many relations are not function.
• A house can't function if someone don't pay the bills of the house so there is no uniqueness.