Question
The number of onto functions that can be defined from A={a,b,c,d,e} to {1,2} is
- 30
- 0
- 60
- 32
Hint:
In this question, the number of onto functions that can be defined from A= {a, b, c, d, e} to {1,2}. Formula to find the number of onto functions from set A to set B We have to find the number of onto functions from a set A with n number of elements to set B with m number of elements. Total number of functions from A to B = 
.
The correct answer is: 32
Given, A= {a, b, c, d, e} and B= {1 ,2}
Element a can has an image in 2 ways, i.e., (1 or 2).
Similarly, a, b, c, d and e can have an image in 5 ways.
Thus, total number of ways =2×2×2×2×2=32
Given, A= {a, b, c, d, e} and B= {1 ,2}
Element a can has an image in 2 ways, i.e., (1 or 2).
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