two step equations math

P(n,r) is the number of permutations of n dissimilar things taken r at a time. These permutations can be divided into two groups. (i) Those not containing a particular thing l . (ii) Those containing a particular thing l . Taking out l from the given things, we have (n-1) things wh..

1. A square matrix A is said to be skew-symmetric if A ' = -A. 2. The diagonal elements of a skew-symmetric matrix are all ze..

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

1. O!= 1 2. When n is a negative or fraction, n! is not defined...

The series of terms a, ar, ar 2 , ar 3 ,.... in which each term bears a constant ratio to the preceeding term is a geometric progression. The constant ratio is called the common rati..

The same principle can be generalized to three or more events occurring in succession as follows: If n operations can be performed in m 1 ,m 2 ,m 3 ,...m n ways respectively, then all n operations in succession can be performed exactly in m 1 ,m 2 ,m 3 ,...m n ways. The above..

Sequence - A set of numbers arranged in a definite order according to some definite rule is called a sequence. or A sequence is a function whose domain is the set N of natural numbers. It is customary to denote a sequence by a letter 'a' and the image a(n) or t(n), n N under 'a' by a n or t ..

When things are arranged in places along a line with first and last place, they form a linear permutation. So far we have dealt only with linear permutations. When things are arranged in places along a closed curve or a circle, in which any place may be regarded as the first or last place, they for..

Question: For the post of 5 teachers, there are 23 applicants. 2 posts are reserved for S.C. candidates and there are 7 S.C. candidates among applicants. In how many ways can the selection be made? Answer: There are 23 applicants. Among this, 7 are S.C. candidates. We have to ..

If A and B are 2 matrices of the same order, then A + B is the sum of the 2 matrices where each element is got by adding corresponding elements of A and B. ..