मराठी
महाराष्ट्र राज्य शिक्षण मंडळएचएससी वाणिज्य (इंग्रजी माध्यम) इयत्ता १२ वी

Find matrix X, if AX = B, where A = and B[123-112124]and B=[123]. - Mathematics and Statistics

Advertisements
Advertisements

प्रश्न

Find matrix X, if AX = B, where A = `[(1, 2, 3),(-1, 1, 2),(1, 2, 4)] "and B" = [(1),(2),(3)]`.

बेरीज

उत्तर

Given,AX = B

∴ `[(1, 2, 3),(-1, 1, 2),(1, 2, 4)] "X" = [(1),(2),(3)]`

Applying R2 → R2 + R3

`[(1, 2, 3),(0, 3, 6),(1, 2, 4)] "X" = [(1),(5),(3)]`

R3 → R3 – R1, we get

`[(1, 2, 3),(0, 3, 6),(0, 0, 1)] "X" = [(1),(5),(2)]`

R2 →`R_2/3`

`[(1, 2, 3),(0, 1, 2),(0, 0, 1)] "X" = [(1),(5/3),(2)]`

Applying R2 → R2 - 2R3

`[(1, 2, 3),(0, 1, 0),(0, 0, 1)] "X" = [(1),(-7/3),(2)]`

R1 → R1 – 3R3

`[(1, 2, 0),(0, 1, 0),(0, 0, 1)] "X" = [(-5),(-7/3),(2)]`

R1 → R1 – 2R2

`[(1, 0, 0),(0, 1, 0),(0, 0, 1)] "X" = [(-1/3),(-7/3),(2)]`

IX = `[(-1/3),(-7/3),(2)]`

X = `[(-1/3),(-7/3),(2)]`

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 2: Matrices - Exercise 2.5 [पृष्ठ ७२]

व्हिडिओ ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्‍न

Find the inverse of matrix A by using adjoint method; where A = `[(1, 0, 1), (0, 2, 3), (1, 2, 1)]`


Find the inverse of the following matrix by elementary row transformations if it exists.
`A = [(1, 2, -2), (0, -2, 1), (-1, 3, 0)]`


Find the co-factor of the element of the following matrix.

`[(1,-1,2),(-2,3,5),(-2,0,-1)]`


If A = `[(1,-1,2),(3,0,-2),(1,0,3)]` verify that A (adj A) = (adj A) A = | A | I


Find the inverse of the following matrix by the adjoint method.

`[(2,-2),(4,3)]`


Choose the correct answer from the given alternatives in the following question:

For a 2 × 2 matrix A, if A(adj A) = `[(10,0),(0,10)]`, then determinant A equals


Choose the correct answer from the given alternatives in the following question:

If A−1 = `- 1/2[(1,-4),(-1,2)]`, then A = ______.


Find the inverse `[(1, 2, 3 ),(1, 1, 5),(2, 4, 7)]` of the elementary row tranformation.


If A = `[(1, 0, 1),(0, 2, 3),(1, 2, 1)] "and B" = [(1, 2, 3),(1, 1, 5),(2, 4, 7)]`, then find a matrix X such that XA = B.


Choose the correct alternative.

If a 3 x 3 matrix B has it inverse equal to B, thenB2 = _______


Fill in the blank :

If A = `[(3, -5),(2, 5)]`, then co-factor of a12 is _______


Fill in the blank :

(AT)T = _______


Fill in the blank :

If A = `[(2, 1),(1, 1)] "and" "A"^-1 = [(1, 1),(x, 2)]`, then x = _______


State whether the following is True or False :

Singleton matrix is only row matrix.


Find inverse of the following matrices (if they exist) by elementary transformations :

`[(2, -3, 3),(2, 2, 3),(3, -2, 2)]`


Find the inverse of `[(3, 1, 5),(2, 7, 8),(1, 2, 5)]` by adjoint method.


The adjoint matrix of `[(3, -3, 4),(2, -3, 4),(0, -1, 1)]` is ______.


If A = `[(0, 0, -1),(0, -1, 0),(-1, 0, 0)]`, then the only correct statement about the matrix A is ______


If A = `[(2, 4),(1, 3)]` and B = `[(1, 1),(0, 1)]` then find (A−1 B−1)


Choose the correct alternative:

If A is a non singular matrix of order 3, then |adj (A)| =  ______


Complete the following activity to verify A. adj (A) = det (A) I.

Given A = `[(2, 0, -1),(5, 1, 0),(0, 1, 3)]` then

|A| = 2(____) – 0(____) + ( ) (____)

= 6 – 0 – 5

= ______ ≠ 0

Cofactors of all elements of matrix A are

A11 = `(-1)^2 |("( )", "( )"),("( )", "( )")|` = (______),

A12 = `(-1)^3 |(5, "( )"),("( )", 3)|` = – 15,

A13 = `(-1)^4 |(5, "( )"),("( )", 1)|` = 5,

A21 = _______, A22 = _______, A23 = _______,

A31 = `(-1)^4 |("( )", "( )"),("( )", "( )")|` = (______),

A32 = `(-1)^5 |(2, "( )"),("( )", 0)|` = (  ),

A33 = `(-1)^6 |(2, "( )"),("( )", 1)|` = 2,.

Cofactors of matrix A = `[(3, "____", "____"),("____", "____",-2),(1, "____", "____")]`

adj (A) = `[("____", "____", "____"),("____", "____","____"),("____","____","____")]`

A.adj (A) = `[(2, 0, -1),(5, 1, 0),(0, 1, 3)] [("( )", -1, 1), (-15, "( )", -5),("( )", -2, "( )")] = [(1, 0, "( )"),("( )", "( )", "( )"),(0, "( )", "( )")]` = |A|I


Solve by matrix inversion method:

3x – y + 2z = 13; 2x + y – z = 3; x + 3y – 5z = - 8


Solve by matrix inversion method:

x – y + 2z = 3; 2x + z = 1; 3x + 2y + z = 4


Solve by matrix inversion method:

2x – z = 0; 5x + y = 4; y + 3z = 5


If A = `[(a,b),(c,d)]` such that ad - bc ≠ 0 then A-1 is


If A = `[(2,3),(1,2)]`, B = `[(1,0),(3,1)]`, then B-1A-1 = ?


If A = `[(4,5),(2,1)]` and A2 - 5A - 6l = 0, then A-1 = ?


If [abc] ≠ 0, then `(["a" + "b b" + "c c" + "a"])/(["b c a"])` = ____________.


If A is non-singular matrix such that (A - 2l)(A - 4l) = 0 then A + 8A-1 = ______.


The inverse of `[(1,cos alpha),(- cos alpha, -1)]` is ______.


Find the cofactors of the elements of the matrix

`[(-1, 2),(-3, 4)]`


Find the inverse of the matrix A by using adjoint method.

where A = `[(-3, -1, 1),(0, 0, 1),(-15, 6, -6)]`


If A = `[(1, 2, -1),(-1, 1, 2),(2, -1, 1)]`, then det (adj (adj A)) is ______.


If A = `[(x, 1),(1, 0)]` and A = A–1, then x = ______.


For a invertible matrix A if A(adjA) = `[(10, 0),(0, 10)]`, then |A| = ______.


If A = `[(2, 2),(-3, 2)]`, B = `[(0, -1),(1, 0)]`, then (B–1 A–1)–1 is equal to ______.


If matrix A = `[(1, -1),(2, 3)]`, then A2 – 4A + 5I is where I is a unit matix.


If A = `[(4, 3, 2),(-1, 2, 0)]`, B = `[(1, 2),(-1, 0),(1, -2)]`

Find (AB)–1 by adjoint method.

Solution:

AB = `[(4, 3, 2),(-1, 2, 0)] [(1, 2),(-1, 0),(1, -2)]`

AB = [  ]

|AB| =  `square`

M11 = –2  ∴ A11 = (–1)1+1 . (–2) = –2

M12 = –3     A12 = (–1)1+2 . (–3) = 3

M21 = 4       A21 = (–1)2+1 . (4) = –4

M22 = 3       A22 = (–1)2+2 . (3) = 3

Cofactor Matrix [Aij] = `[(-2, 3),(-4, 3)]`

adj (A) = [  ]

A–1 = `1/|A| . adj(A)`

A–1 = `square`


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×