हिंदी

Find the Inverse of the Following Matrix and Verify that a − 1 a = I 3 ⎡ ⎢ ⎣ 2 3 1 3 4 1 3 7 2 ⎤ ⎥ ⎦ - Mathematics

Advertisements
Advertisements

प्रश्न

Find the inverse of the following matrix and verify that \[A^{- 1} A = I_3\]

\[\begin{bmatrix}2 & 3 & 1 \\ 3 & 4 & 1 \\ 3 & 7 & 2\end{bmatrix}\]

उत्तर

\[B = \begin{bmatrix}2 & 3 & 1 \\ 3 & 4 & 1 \\ 3 & 7 & 2\end{bmatrix}\]
Now, 
\[ C_{11} = \begin{vmatrix}4 & 1 \\ 7 & 2\end{vmatrix} = 1, C_{12} = - \begin{vmatrix}3 & 1 \\ 3 & 2\end{vmatrix} = - 3\text{ and }C_{13} = \begin{vmatrix}3 & 4 \\ 3 & 7\end{vmatrix} = 9\]
\[ C_{21} = - \begin{vmatrix}3 & 1 \\ 7 & 2\end{vmatrix} = 1, C_{22} = \begin{vmatrix}2 & 1 \\ 3 & 2\end{vmatrix} = 1\text{ and } C_{23} = - \begin{vmatrix}2 & 3 \\ 3 & 7\end{vmatrix} = - 5\]
\[ C_{31} = \begin{vmatrix}3 & 1 \\ 4 & 1\end{vmatrix} = - 1, C_{32} = - \begin{vmatrix}2 & 1 \\ 3 & 1\end{vmatrix} = 1\text{ and }C_{33} = \begin{vmatrix}2 & 3 \\ 3 & 4\end{vmatrix} = - 1\]
\[adjB = \begin{bmatrix}1 & - 3 & 9 \\ 1 & 1 & - 5 \\ - 1 & 1 & - 1\end{bmatrix}^T = \begin{bmatrix}1 & 1 & - 1 \\ - 3 & 1 & 1 \\ 9 & - 5 & - 1\end{bmatrix}\]
\[\text{ and }\left| B \right| = 2\]
\[ B^{- 1} = \frac{1}{2}\begin{bmatrix}1 & 1 & - 1 \\ - 3 & 1 & 1 \\ 9 & - 5 & - 1\end{bmatrix}\]
\[\text{ Now, }B^{- 1} B = \begin{bmatrix}1 & 0 & 0 \\ 0 & 1 & 0 \\ 0 & 0 & 1\end{bmatrix} = I_3\]

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 7: Adjoint and Inverse of a Matrix - Exercise 7.1 [पृष्ठ २३]

APPEARS IN

आरडी शर्मा Mathematics [English] Class 12
अध्याय 7 Adjoint and Inverse of a Matrix
Exercise 7.1 | Q 9.2 | पृष्ठ २३

संबंधित प्रश्न

Verify A (adj A) = (adj A) A = |A|I.

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


Find the inverse of the matrices (if it exists).

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


Find the inverse of the matrices (if it exists).

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


Find the inverse of the matrices (if it exists).

`[(2,1,3),(4,-1,0),(-7,2,1)]`


For the matrix A = `[(3,2),(1,1)]` find the numbers a and b such that A2 + aA + bI = O.


For the matrix A = `[(1,1,1),(1,2,-3),(2,-1,3)]` show that A3 − 6A2 + 5A + 11 I = O. Hence, find A−1.


If A is an invertible matrix of order 2, then det (A−1) is equal to ______.


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

  1. [adj A]–1 = adj (A–1)
  2. (A–1)–1 = A

Find the adjoint of the following matrix:

\[\begin{bmatrix}1 & \tan \alpha/2 \\ - \tan \alpha/2 & 1\end{bmatrix}\]
Verify that (adj A) A = |A| I = A (adj A) for the above matrix.

If  \[A = \begin{bmatrix}- 4 & - 3 & - 3 \\ 1 & 0 & 1 \\ 4 & 4 & 3\end{bmatrix}\], show that adj A = A.


Find A (adj A) for the matrix  \[A = \begin{bmatrix}1 & - 2 & 3 \\ 0 & 2 & - 1 \\ - 4 & 5 & 2\end{bmatrix} .\]


Find the inverse of the following matrix:

\[\begin{bmatrix}a & b \\ c & \frac{1 + bc}{a}\end{bmatrix}\]

Find the inverse of the following matrix:

\[\begin{bmatrix}2 & 5 \\ - 3 & 1\end{bmatrix}\]

Find the inverse of the following matrix.

\[\begin{bmatrix}0 & 1 & - 1 \\ 4 & - 3 & 4 \\ 3 & - 3 & 4\end{bmatrix}\]

Let \[A = \begin{bmatrix}3 & 2 \\ 7 & 5\end{bmatrix}\text{ and }B = \begin{bmatrix}6 & 7 \\ 8 & 9\end{bmatrix} .\text{ Find }\left( AB \right)^{- 1}\]


If \[A = \begin{bmatrix}4 & 5 \\ 2 & 1\end{bmatrix}\] , then show that \[A - 3I = 2 \left( I + 3 A^{- 1} \right) .\]


Find the inverse of the matrix \[A = \begin{bmatrix}a & b \\ c & \frac{1 + bc}{a}\end{bmatrix}\] and show that \[a A^{- 1} = \left( a^2 + bc + 1 \right) I - aA .\]


Show that the matrix, \[A = \begin{bmatrix}1 & 0 & - 2 \\ - 2 & - 1 & 2 \\ 3 & 4 & 1\end{bmatrix}\]  satisfies the equation,  \[A^3 - A^2 - 3A - I_3 = O\] . Hence, find A−1.


If \[A = \begin{bmatrix}- 1 & 2 & 0 \\ - 1 & 1 & 1 \\ 0 & 1 & 0\end{bmatrix}\] , show that  \[A^2 = A^{- 1} .\]


Solve the matrix equation \[\begin{bmatrix}5 & 4 \\ 1 & 1\end{bmatrix}X = \begin{bmatrix}1 & - 2 \\ 1 & 3\end{bmatrix}\], where X is a 2 × 2 matrix.


If \[A = \begin{bmatrix}1 & 2 & 2 \\ 2 & 1 & 2 \\ 2 & 2 & 1\end{bmatrix}\] , find \[A^{- 1}\] and prove that \[A^2 - 4A - 5I = O\]


If \[A = \begin{bmatrix}1 & - 2 & 3 \\ 0 & - 1 & 4 \\ - 2 & 2 & 1\end{bmatrix},\text{ find }\left( A^T \right)^{- 1} .\]


Find the inverse by using elementary row transformations:

\[\begin{bmatrix}7 & 1 \\ 4 & - 3\end{bmatrix}\]


Find the inverse by using elementary row transformations:

\[\begin{bmatrix}1 & 6 \\ - 3 & 5\end{bmatrix}\]


Find the inverse by using elementary row transformations:

\[\begin{bmatrix}2 & 5 \\ 1 & 3\end{bmatrix}\]


Find the inverse by using elementary row transformations:

\[\begin{bmatrix}0 & 1 & 2 \\ 1 & 2 & 3 \\ 3 & 1 & 1\end{bmatrix}\]


If A is symmetric matrix, write whether AT is symmetric or skew-symmetric.


If A is an invertible matrix such that |A−1| = 2, find the value of |A|.


Find the inverse of the matrix \[\begin{bmatrix} \cos \theta & \sin \theta \\ - \sin \theta & \cos \theta\end{bmatrix}\]


If \[A = \begin{bmatrix}3 & 4 \\ 2 & 4\end{bmatrix}, B = \begin{bmatrix}- 2 & - 2 \\ 0 & - 1\end{bmatrix},\text{ then }\left( A + B \right)^{- 1} =\]


If A is a singular matrix, then adj A is ______.


If B is a non-singular matrix and A is a square matrix, then det (B−1 AB) is equal to ___________ .


If A5 = O such that \[A^n \neq I\text{ for }1 \leq n \leq 4,\text{ then }\left( I - A \right)^{- 1}\] equals ________ .


If \[A = \begin{bmatrix}2 & - 1 \\ 3 & - 2\end{bmatrix},\text{ then } A^n =\] ______________ .

Find A−1, if \[A = \begin{bmatrix}1 & 2 & 5 \\ 1 & - 1 & - 1 \\ 2 & 3 & - 1\end{bmatrix}\] . Hence solve the following system of linear equations:x + 2y + 5z = 10, x − y − z = −2, 2x + 3y − z = −11


If A = `[(1/sqrt(5), 2/sqrt(5)),((-2)/sqrt(5), 1/sqrt(5))]`, B = `[(1, 0),(i, 1)]`, i = `sqrt(-1)` and Q = ATBA, then the inverse of the matrix A. Q2021 AT is equal to ______.


If for a square matrix A, A2 – A + I = 0, then A–1 equals ______.


Given that A is a square matrix of order 3 and |A| = –2, then |adj(2A)| is equal to ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×