Question

If A={1,2} and B={-1,0,1,2} How many functions are possible from B to A?

Answer 1

Answer:

A={1,2,3,4} and B={a,b,c}

Let number of elements of A be r and number of elements of B be m.

⇒ Number of elements of set A=r=4

⇒ Number of elements of set B=n=3

Here, we can see r>n.

One-one function is only possible from A to B if number of elements in B is greater than number of elements in A.

∴ The total number of one-one function from A to B is 0.