JEE Mains · Maths · STD 11 - 6. permutation and combination
The number of singular matrices of order 2 , whose elements are from the set \(\{2,3,6,9\}\) is
- A 32
- B 34
- C 36
- D 38
Answer & Solution
Correct Answer
(C) 36
Step-by-step Solution
Detailed explanation
\(\left|\begin{array}{ll} \mathrm{a} & \mathrm{~d} \\ \mathrm{~b} & \mathrm{c} \end{array}\right|=\mathrm{ad}-\mathrm{bc} \Rightarrow \mathrm{ad}=\mathrm{bc}\) Case-I Exactly 1 no. is used \(\Rightarrow \text { All singular }={ }^4 \mathrm{C}_1\) Case-II Exactly 2 no. is used…
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