If for three matrices 𝐴=[π‘Žπ‘–π‘—]π‘šΓ—4 , B=[𝑏𝑖𝑗]𝑛×3 π‘Žπ‘›π‘‘ C=[𝑐𝑖 - CBSE Class 1 - CBSE Class 12 Sample Paper for 2026 Boards

part 2 - Question 2 - CBSE Class 12 Sample Paper for 2026 Boards - Solutions of Sample Papers and Past Year Papers - for Class 12 Boards - Class 12
part 3 - Question 2 - CBSE Class 12 Sample Paper for 2026 Boards - Solutions of Sample Papers and Past Year Papers - for Class 12 Boards - Class 12

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Question 2 If for three matrices 𝐴=[π‘Ž_𝑖𝑗 ]_(π‘šΓ—4)," " B=[𝑏_𝑖𝑗 ]_(𝑛×3) and C=[𝑐_𝑖𝑗 ]_(π‘Γ—π‘ž) products 𝐴𝐡 and 𝐴𝐢 both are defined and are square matrices of same order, then value of π‘š,𝑛,𝑝 and π‘ž are: (A) π‘š=π‘ž=3 and 𝑛=𝑝=4 (B) π‘š=2,π‘ž=3 and 𝑛=𝑝=4 (C) π‘š=π‘ž=4 and 𝑛=𝑝=3 (D) π‘š=4,𝑝=2 and 𝑛=π‘ž=3 Let’s check both AB and AC separately For AB Order of A is m Γ— 4 Order of B is n Γ— 3 AB = [π‘Ž_𝑖𝑗 ]_(m Γ— 4) [𝑏_𝑖𝑗 ]_(𝑛×3) This is possible only if n = 4 And, order of AB is m Γ— 3 Since AB is square matrix Both m and 3 should be equal ∴ m = 3 For AC Order of A is m Γ— 4 Order of C is p Γ— q AB = [π‘Ž_𝑖𝑗 ]_(m Γ— 4) [𝑐_𝑖𝑗 ]_(π‘Γ—π‘ž) This is possible only if p = 4 And, order of AC is m Γ— q i.e. 3 Γ— q Since AB is square matrix Both 3 and q should be equal ∴ q = 3 Thus, m = q = 3 n = p = 4 So, the correct answer is (A)

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