3 and 4 .Determinants and Matrices
medium

माना एक वर्ग आव्यूह $\mathrm{A}$ के लिए $\mathrm{AA}^{\mathrm{T}}=\mathrm{I}$ है। तो $\frac{1}{2} \mathrm{~A}\left[\left(\mathrm{~A}+\mathrm{A}^{\mathrm{T}}\right)^2+\left(\mathrm{A}-\mathrm{A}^{\mathrm{T}}\right)^2\right]$ बराबर है

A

 $A^2+I$

B

$A^3+I$

C

 $A^2+A^T$

D

 $A^3+A^T$

(JEE MAIN-2024)

Solution

$\mathrm{AA}^{\mathrm{T}}=\mathrm{I}=\mathrm{A}^{\mathrm{T}} \mathrm{A}$

On solving given expression, we get

$ \frac{1}{2} A\left[A^2+\left(A^T\right)^2+2 A A^T+A^2+\left(A^T\right)^2-2 A A^T\right] $

$ =A\left[A^2+\left(A^T\right)^2\right]=A^3+A^T$

Standard 12
Mathematics

Similar Questions

Start a Free Trial Now

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