let a {1,2,3,4} then number of one -one functions f a -> a such that f(i) not equal to i total number of 1-1 functions here will be 4! but then there's a restriction in the question how do we do that
let a {1,2,3,4} then number of one -one functions f a -> a such that f(i) not equal to i
total number of 1-1 functions here will be 4!
but then there's a restriction in the question how do we do that