how to use discrete mathematics

Now we shall discuss the use of determinants in finding the area of a triangle and in the solution of simultaneous equation..

Using matrix method solve the following systems of linear equations 2x - y + z = -3 3x - z = - 8 2x + 6y ..

Using matrix method, solve the following system of linear equations x + y + z = 6 (1) x + 2y + 3z = 14 (2) x + 4y + 7z = 30 ..

Permutations - The different arrangements that can be made with a given number of things taking some or all of them at a time are called permutations. The symbol n P r or P(n,r) is used to denote the number of permutations of n things taken r at a tim..

Question: How many three letter words (with or without meaning) can be formed out of the letters of the word LOGARITHMS if repetition of letters is not allowed? Answer: Number of letters in the word LOGARITHMS is 10. The three letter words formed by using these lette..

Conclusion - We have seen the application of matrices and determinants in solving system of linear equation with three unknown variables. Matrices and determinants are also widely used in solving large system of linear equation. Some of these methods are Gauss-elimination method, Gauss-Jo..

Matrices - Consider the arrangement In this arrangement, there are two rows and four columns. The number 3 lies in the 2 n d row and 4 t h column. Each number has a fixed position. Matrix A has 2 rows and 3 columns and is thus of order 2 x 3. Matrix B has 3 rows and 2 columns and is thus of order 3..

Using determinants, find the area of triangle whose vertices are (2, -7), (1, 3), (10, 8). Solution: (x 1 , y 1 ) = (2, -7) (x 2 , y 2 ) = (1, 3) (x 3 , y 3 ) = (10, 8) Area of the triangle = -47.5 Since area has to be a positive quantity, it is given by 47.5 sq.uni..

If a system of linear equations has at least one solution, then the system is called consistent, otherwise it is called inconsistent. Solve the system of linear equations (1) by using method of elimination as studied earlier Multiplying the first equation by a 2 and the second equation ..

(iii) If 'a' and 'd' be the first term and common difference of the A.P. {T n }, then the sum of first n terms, S n is given by The form (a) is used when common difference 'd' is known and the form (b) is used when the last term 'l' is known. (iv) T 1 = S 1 and for n > 1, we ..