Question:

If $A = \begin{bmatrix}a&b\\ b&a\end{bmatrix}$ and $A^{2}\begin{bmatrix}\alpha&\beta \\ \beta&\alpha\end{bmatrix}$, then

Updated On: Jul 28, 2022
  • $\alpha = 2ab , \beta = a^2 + b^2$
  • $\alpha = a^2 + b^2 , \beta = ab $
  • $\alpha = a^2 + b^2 , \beta = 2ab$
  • $\alpha = a^2 + b^2 , \beta = a^2 - b^2$
Hide Solution
collegedunia
Verified By Collegedunia

The Correct Option is C

Solution and Explanation

$ A^{2}\begin{bmatrix}\alpha&\beta \\ \beta&\alpha\end{bmatrix} $ $ \Rightarrow\begin{bmatrix}\alpha&\beta\\ \beta&\alpha\end{bmatrix} = \begin{bmatrix}a&b\\ b&a\end{bmatrix}\begin{bmatrix}a&b\\ b&a\end{bmatrix} $ $ \Rightarrow \begin{bmatrix}\alpha&\beta\\ \beta&\alpha\end{bmatrix} = \begin{bmatrix}a^{2} +b^{2}&2ab\\ 2ab&a^{2}+b^{2}\end{bmatrix} $ $ \Rightarrow \alpha = a^{2}+b^{2}$ and $ 2ab = \beta$
Was this answer helpful?
0
0

Concepts Used:

Matrices

Matrix:

A matrix is a rectangular array of numbers, variables, symbols, or expressions that are defined for the operations like subtraction, addition, and multiplications. The size of a matrix is determined by the number of rows and columns in the matrix.

The basic operations that can be performed on matrices are:

  1. Addition of Matrices - The addition of matrices addition can only be possible if the number of rows and columns of both the matrices are the same.
  2. Subtraction of Matrices - Matrices subtraction is also possible only if the number of rows and columns of both the matrices are the same.
  3. Scalar Multiplication - The product of a matrix A with any number 'c' is obtained by multiplying every entry of the matrix A by c, is called scalar multiplication. 
  4. Multiplication of Matrices - Matrices multiplication is defined only if the number of columns in the first matrix and rows in the second matrix are equal. 
  5. Transpose of Matrices - Interchanging of rows and columns is known as the transpose of matrices.