3 and 4 .Determinants and Matrices
easy

જો $A = \left[ {\begin{array}{*{20}{c}}i&0\\0&i\end{array}} \right]$, તો ${A^2} = $

A

$\left[ {\begin{array}{*{20}{c}}1&0\\0&{ - 1}\end{array}} \right]$

B

$\left[ {\begin{array}{*{20}{c}}{ - 1}&0\\0&{ - 1}\end{array}} \right]$

C

$\left[ {\begin{array}{*{20}{c}}1&0\\0&1\end{array}} \right]$

D

$\left[ {\begin{array}{*{20}{c}}{ - 1}&0\\0&1\end{array}} \right]$

Solution

(b) $A = \left[ {\begin{array}{*{20}{c}}i&0\\0&i\end{array}} \right]$; ${A^2} = A.\,A = \left[ {\begin{array}{*{20}{c}}i&0\\0&i\end{array}} \right]\,\left[ {\begin{array}{*{20}{c}}i&0\\0&i\end{array}} \right]$

${A^2} = \left[ {\begin{array}{*{20}{c}}{ – 1}&0\\0&{ – 1}\end{array}} \right]$,

$[\because {i^2} =  – 1]$ . 

Standard 12
Mathematics

Similar Questions

Start a Free Trial Now

Confusing about what to choose? Our team will schedule a demo shortly.