Pleasesir help me to solve this question ...I m not able to solve it ...Please sir
Kunal chavan , 3 Years ago
Grade 12
IIT JEE Entrance Exam> Pleasesir help me to solve this question ...
1 Answers
Abhishek Singh
Last Activity: 3 Years ago
clearly f:A → A ==> image of A is mapped to A.
Consider x in A , if f(x) = y, Then following 2 result can be seen
1) f(y) = f(f(x))= fof(x) = x
2) f(x) = f(f(y)) = fof(y) = y
Thus If we choose any 2 number (repetition may occur) ==> their images will just swap
==> This is equivalent to choosing pairs in in set of 4 . Following case arise
1) 2 Pairs each with distinct number ==> 4C2 ways = 6
2) 1 Pair of distinct and other 2 numbers mapped to them selves = 4c2 ways
3) All numbers mapped to themselves(identity map) = 1 way
Thus 13 such functions can be made
Provide a better Answer & Earn Cool Goodies
Enter text here...
LIVE ONLINE CLASSES
Prepraring for the competition made easy just by live online class.
Full Live Access
Study Material
Live Doubts Solving
Daily Class Assignments
Ask a Doubt
Get your questions answered by the expert for free
Enter text here...
Other Related Questions on IIT JEE Entrance Exam
My rank is 29k, General, should I opt for any state college cse branch or some Nits in which in which I am getting ECE , chemical, mechanics etc....
IIT JEE Entrance Exam
0 Answer Available
Last Activity: 2 Year ago(s)
How is Ranquer Eduzone,comparing, Akash,Fitjee,Resonance,Naryana
IIT JEE Entrance Exam
0 Answer Available
Last Activity: 2 Year ago(s)
Can class 9th students study syllabus classof 11th
IIT JEE Entrance Exam
3 Answer Available
Last Activity: 2 Year ago(s)
I m foreigner,How much mark i need to get into IIT??
IIT JEE Entrance Exam
1 Answer Available
Last Activity: 2 Year ago(s)