Determinants Matrices Question 64

Question: Let $ A={{[a _{ij}]} _{m\times m}} $ be a matrix and $ C={{[c _{ij}]} _{m\times m}} $ be another matrix where $ c _{ij} $ is the cofactor of $ a _{ij} $ Then, what is the value of $ |AC| $ -

Options:

A) $ |A{{|}^{m-1}} $

B) $ |A{{|}^{m}} $

C) $ |A{{|}^{m+1}} $

D) Zero

Show Answer

Answer:

Correct Answer: C

Solution:

  • [c] Let $ A={{[a _{ij}]} _{m\times m}} $ be a matrix and $ C={{[c _{ij}]} _{m\times m}} $ be another matrix where $ c _{ij} $ is the cofactor of $ a _{ij} $
    $ \therefore $ The value of $ | AC |={{| A |}^{m+1}} $