math test

The matrices are identify matrices of order 2 and 3 respectivel..

Each circular permutation corresponds to n linear permutations depending on where we start. Since there are exactly n! linear permutations, there are exactly permutations. Hence, the number of circular permutations is the same as (n-1)..

We are to select 4 students from 32. This selection can done i..

C(n,r) is the required combination by definition. Each of these combinations consists of a group of r dissimilar things, which can be arranged among themselves in P(r,r) = r! ways. But the number of permutations of n different things taken r at a time is P(n,r)..

If r = s, there is nothing to prove. Now, If r < s, then n - r > n - s, then the above equation becomes Since both sides are products of (s-r), consecutive integers in Similarly it can be proved that n = r + s if r > s...

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8! = 8 x 7 x 6 x 5 x4 x 3 x 2 x 1 = 40320 ..

1. 2 and 3 are two digits and with these digits, the numbers 32 and 23 are formed. Although both numbers viz., 32 and 23 consist of the digits 2 and 3, the order of digits is different. Each of the above arrangements is called a 'permutation'. Thus, the number of arrangements or permutations of tw..