Let f : A-->B be an onto function where A={1,2,3,4} B = {x,y,z} also f(!) = x
Let M be total such functions then find value of M/2
-
UP 0 DOWN 0 0 2
2 Answers
62if f(1) = x
then f(2) can either be x or y or z
same with 3, 4
thus, there are 33 = 27 such functions....
Out of these, we want only onto functions..
No of functions which dont have z in their range =23
No of functions which dont have y in their range =23
No fo functions which dont have both y and z in their range = 1
Thus, M= 27-8-8+1 = 12
M/2 = 6
