Mathematics · 2021
JEE Main · 25 February 2021, Shift 2 · Q61
If for the matrix, A= [1, -α; α, β], A A^T=I_2, then the value of α^4+β^4 is:
If for the matrix, $\displaystyle A=\left[\begin{array}{cc}1 & -\alpha \\ \alpha & \beta\end{array}\right], A A^T=I_2$, then the value of $\displaystyle \alpha^4+\beta^4$ is :
Official answer
(2)
$\displaystyle 1$
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