Question 3 - CBSE Class 12 Sample Paper for 2026 Boards - Solutions of Sample Papers and Past Year Papers - for Class 12 Boards

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Question 3 If the matrix 𝐴=[■(0&𝑟&−2@3&𝑝&𝑡@𝑞&−4&0)] is skew-symmetric, then value of (𝑞 + 𝑡)/(𝑝 + 𝑟) is.... (A) -2 (B) 0 (C) 1 (D) 2In a skew symmetric matrix A’ = −A Putting values [■(0&𝑟&−2@3&𝑝&𝑡@𝑞&−4&0)]=−[■(0&3&𝑞@𝑟&𝑝&−4@−2&t&0)] [■(0&𝑟&−2@3&𝑝&𝑡@𝑞&−4&0)]=[■(−0&−3&−𝑞@−𝑟&−𝑝&−(−4)@−(−2)&−t&−0)] [■(0&𝑟&−2@3&𝑝&𝑡@𝑞&−4&0)]=[■(0&−3&−𝑞@−𝑟&−𝑝&4@2&−t&0)] Since matrices are equal, its corresponding terms are equal. So, r = −3 t = 4 q = 2 And, p = −p p + p = 0 2p = 0 p = 0 Now, we need to find (𝒒 + 𝒕)/(𝒑 + 𝒓)=(2 + 4)/(0 + (−3)) = 6/(−3) = (−6)/3 = –2 So, the correct answer is (A)