**Many-one Function**

A function f: A→ B is said to be many-one if two or more than two elements in A have the same image in B.

**Example:**

Let A = {-1, 1, 2, 3} and B = {1, 4, 9}

Let f: A → B: f(x) = x^{2} Ɐ x ∈ A

Then, each element in A has a unique image under f in B

f is a function from A to B such that

f(-1) = (-1)^{2} = 1

f(1) = 1^{2} = 1

f(2) = 2^{2} = 4

f(3) = 3^{2} = 9

Here, two elements namely -1 and 1 have same image 1 ∈ B.

**Hence, f is many-one.**