Permutation ï»¿
A permutation, also called an "arrangement number" or "order," is a rearrangement of the elements of an ordered list S into a one-to-one correspondence with S itself. The number of permutations on a set of nelements is given by n! (n factorial; For example, there are 2!=2·1=2 permutations of {1,2}, namely {1,2}and {2,1}, and 3!=3·2·1=6 permutations of {1,2,3}, namely {1,2,3}, {1,3,2}, {2,1,3}, {2,3,1}, {3,1,2}, and {3,2,1}. The number of ways of obtaining an ordered subset of k elements from a set of n elements is given byï»¿
You will get a detailed knowledge at the given below different links :
http://www.studyadda.com/videos/jee-mathematics-lectures/permutations-combinations/factorial-1/1611
http://www.studyadda.com/videos/jee-mathematics-lectures/permutations-combinations/permutations-2/1612
http://www.studyadda.com/videos/jee-mathematics-lectures/permutations-combinations/permutations-3/1613
http://www.studyadda.com/videos/jee-mathematics-lectures/permutations-combinations/permutations-4/1614
http://www.studyadda.com/videos/jee-mathematics-lectures/permutations-combinations/permutations-5/1615
http://www.studyadda.com/videos/jee-mathematics-lectures/permutations-combinations/permutations-6/1616
http://www.studyadda.com/videos/jee-mathematics-lectures/permutations-combinations/permutations-7/1617
http://www.studyadda.com/videos/jee-mathematics-lectures/permutations-combinations/permutations-8/1618
http://www.studyadda.com/videos/jee-mathematics-lectures/permutations-combinations/permutations-9/1619
http://www.studyadda.com/videos/jee-mathematics-lectures/permutations-combinations/permutations-10/1620ï»¿ï»¿ï»¿ï»¿ï»¿
http://www.studyadda.com/videos/jee-mathematics-lectures/permutations-combinations/permutations-11/1621
http://www.studyadda.com/videos/jee-mathematics-lectures/permutations-combinations/permutations-12/1622
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