COMEDK · Maths · 22. Determinants
If \(A=\left[\begin{array}{ccc}\cos \theta & -\sin \theta & 0 \\ \sin \theta & \cos \theta & 0 \\ 0 & 0 & 1\end{array}\right]\), the cofactor of \(a_{32}\) are
- A \(1,-1\)
- B 0,1
- C \(-1,0\)
- D 0,0
Answer & Solution
Correct Answer
(D) 0,0
Step-by-step Solution
Detailed explanation
We have, \(A=\left[\begin{array}{ccc} \cos \theta & -\sin \theta & 0 \\ \sin \theta & \cos \theta & 0 \\ 0 & 0 & 1 \end{array}\right]\) Minor of \(a_{32}=\left|\begin{array}{cc}\cos \theta & 0 \\ \sin \theta & 0\end{array}\right|=0-0=0\) and cofactor of \(a_{32}=-\) Minor of…
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