MCQ
$\left|\begin{array}{cc}a+i b & c+i d \\ -c+i d & a-i b\end{array}\right|=$
  • A
    $(a+b)^2$
  • B
    $(a+b+c+d)^2$
  • C
    $\left(a^2+b^2-c^2-d^2\right)$
  • $a^2+b^2+c^2+d^2$

Answer

Correct option: D.
$a^2+b^2+c^2+d^2$
(d): We have, $\left|\begin{array}{cc}a+i b & c+i d \\ -c+i d & a-i b\end{array}\right|$

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