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

Find inverse of the following matrices (if they exist) by elementary transformations : [20-1510013] - Mathematics and Statistics

Advertisements
Advertisements

प्रश्न

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

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

बेरीज

उत्तर

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

∴ |A| = `|(2, 0, -1),(5, 1, 0),(0, 1, 3)|`

= 2(3 – 0) –0 –1(5 – 0)
= 6 – 0 – 5
= 1 ≠ 0
∴ A–1 existts.
Consider AA–1 = I

∴ `[(2, 0, 1),(5, 1, 0),(0, 1, 3)] "A"^-1 = [(1, 0, 0),(0, 1, 0),(0, 0, 1)]`

Applying R1 ↔ R2, we get

`[(5, 1, 0),(2, 0, -1),(0, 1, 3)] "A"^-1 = [(-2, 1, 0),(1, 0, 0),(0, 0, 1)]`

Applying R1 → R1 – 2R2, we get

`[(1, 1, 2),(2, 0, -1),(0, 1, 3)] "A"^-1 = [(-2, 1, 0),(1, 0, 0),(0, 0, 1)]`

Applying R2 → R2 – 3R3, we get

`[(1, 1, 2),(0, 1, 4),(0, 1, 3)] "A"^-1 = [(-2, 1, 0),(5, -2, 3),(0, 0, 1)]`

Applying R1 → R1 – R2 and R3 → R3 – R2 , we get

`[(1, 0, -2),(0, 1, 4),(0, 0, -1)] "A"^-1 = [(-7, 3, -3),(5, -2, 3),(-5, 2, -2)]`

Applying R3 → (– 1) R3, we get

`[(1, 0, -2),(0, 1, 4),(0, 0, 1)] "A"^-1 = [(-7, 3, -3),(5, -2, 3),(5, -2, 2)]`

Applying R1 → R1 + 2R3 and R2 → R2 – 4R3 , we get

`[(1, 0, 0),(0, 1, 0),(0, 0, 1)] "A"^-1 = [(3, -1, 1),(-15, 6, -5),(5, -2, 2)]`

∴ A–1 = `[(3, -1, 1),(-15, 6, -5),(5, -2, 2)]`.

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 2: Matrices - Miscellaneous Exercise 2 [पृष्ठ ८५]

APPEARS IN

बालभारती Mathematics and Statistics 1 (Commerce) [English] 12 Standard HSC Maharashtra State Board
पाठ 2 Matrices
Miscellaneous Exercise 2 | Q 4.16 | पृष्ठ ८५

व्हिडिओ ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्‍न

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 inverse of the following matrix.

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


Find the inverse of the following matrix.

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


Find the inverse of the following matrix.

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


Find the inverse of the following matrix (if they exist):

`((1,-1),(2,3))`


Find the inverse of the following matrix (if they exist):

`[(2,1),(7,4)]`


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

The inverse of A = `[(0,1,0),(1,0,0),(0,0,1)]` is


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

The inverse of a symmetric matrix is


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 of the following matrices by the adjoint method `[(3, -1),(2, -1)]`.


Find the inverse of the following matrices by the adjoint method `[(2, -2),(4, 5)]`.


Find the inverse of the following matrices by the adjoint method `[(1, 2, 3),(0, 2, 4),(0, 0, 5)]`.


Find the inverse of the following matrices by transformation method:

`[(2, 0, −1),(5, 1, 0),(0, 1, 3)]`


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 A2 + mA + nI = O and n ≠ 0, |A| ≠ 0, then A–1 = _______


Choose the correct alternative.

If A is a 2 x 2 matrix such that A(adj. A) = `[(5, 0),(0, 5)]`, then |A| = _______


Solve the following :

If A = `[(2, -3),(3, -2),(-1, 4)],"B" = [(-3, 4, 1),(2, -1, -3)]`, verify (3A – 5BT)T = 3AT – 5B.


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

`[(2, 1),(7, 4)]`


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

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


The solution (x, y, z) of the equation `[(1, 0, 1),(-1, 1, 0),(0, -1, 1)] [(x),(y),(z)] = [(1),(1),(2)]` is (x, y, z) =


If A = `[(3, 0, 0),(0, 3, 0),(0, 0, 3)]`, then |A| |adj A| = ______


If A = `[(1, -1, 1),(2, 1, -3),(1, 1, 1)]`, 10B = `[(4, 2,2),(-5, 0, ∞),(1, -2, 3)]` and B is the inverse of matrix A, then α = ______


If A = `[(1, 2, 3),(1, 1, 5),(2, 4, 7)]`, then find the value of a31A31 + a32A32 + a33A33.


For an invertible matrix A, if A . (adj A) = `[(10, 0),(0, 10)]`, then find the value of |A|.


If A = `[(3, 1),(5, 2)]`, and AB = BA = I, then find the matrix B


If A = `[(1, 2),(3, -2),(-1, 0)]` and B = `[(1, 3, 2),(4, -1, 3)]` then find the order of AB


Find the adjoint of matrix A = `[(6, 5),(3, 4)]`


Find the adjoint of matrix A = `[(2, 0, -1),(3, 1, 2),(-1, 1, 2)]`


The value of Minor of element b22 in matrix B = `[(2, -2),(4, 5)]` is ______


Find the inverse of the following matrix:

`[(1,2,3),(0,2,4),(0,0,5)]`


Show that the matrices A = `[(2,2,1),(1,3,1),(1,2,2)]` and B = `[(4/5,(-2)/5,(-1)/5),((-1)/5,3/5,(-1)/5),((-1)/5,(-2)/5,4/5)]` are inverses of each other.


Solve by matrix inversion method:

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


If A = `[(2, 0, -1), (5, 1, 0), (0, 1, 3)]` and A−1 = `[(3, -1, 1), (α, 6, -5), (β, -2, 2)]`, then the values of α and β are, respectively.


If A = `[(-i, 0),(0, i)]`, then ATA is equal to


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 ______.


Matrix A = `[(1, 2, 3),(1, 1, 5),(2, 4, 7)]` then the value of a31 A31 + a32 A32 + a33 A33 is ______.


If A = `[(cos α, sin α),(- sin α, cos α)]`, then the matrix A is ______.


If A = `[(1, 2),(3, 4)]` verify that A (adj A) = (adj A) A = |A| I


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×