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Question 6 - CBSE Class 12 Sample Paper for 2021 Boards - Solutions of Sample Papers and Past Year Papers - for Class 12 Boards

Last updated at Oct. 27, 2020 by

Let A = [π‘Žπ‘–π‘—] be a square matrix of order 3Γ—3 and |A|= -7. Find the value of
π‘Ž 11 𝐴 21 + π‘Ž 12 𝐴 22 + π‘Ž 13 𝐴 23Β  where 𝐴 𝑖𝑗 is the cofactor of element π‘Ž 𝑖j

Let A = [aij] be a square matrix of order 3Γ—3 and |A|= -7. Find value

Β 

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Question 6 Let A = [π‘Žπ‘–π‘—] be a square matrix of order 3 Γ— 3 and |A|= βˆ’7. Find the value of π‘Ž11 𝐴21 + π‘Ž12 𝐴22 + π‘Ž13 𝐴23 where 𝐴𝑖𝑗 is the cofactor of element π‘Žπ‘–j We know that ο»ΏIf elements of a row (or column) are multiplied with cofactors of any other row (or column), then their sum is zero Thus, π‘Ž11 𝐴21 + π‘Ž12 𝐴22 + π‘Ž13 𝐴23 = 0

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