Question

If set A contains 8 elements and set B contains 10 elements, number of one to one functions from set A to set B is

• A. 8¹⁰
• B. 10⁸
• C. 80
• D. $10P_{8}$

Answer 1

Answer: (D)

$10P_{8}$

Answer 2

First element of set A can correspond to any of 10 elements of set B. Similarly 2^nd element of set A can be correspond to any of the remaining 9 elements and third element can correspond to any of the 8 elements, and so on.

∴ Required ways = 10 x 9 x 8 x 7 x 6 x 5 x 4 x 3

= $\frac{10!}{2!} =^{10}P_{8}$