Skip to main contentSkip to solution

If A is a 3x3 matrix then:

Match the LIST-I with LIST-II

LIST-ILIST-II
A.∣adjA∣\vert adj A\vertI.∣A∣−1\vert A\vert^{-1}
B.∣A.adjA∣\vert A.adj A\vertII.∣A∣\vert A\vert
C.∣A−1∣\vert A^{-1}\vertIII.∣A∣2\vert A\vert^2
D.∣A−1.adjA∣\vert A^{-1}.adj A\vertIV.∣A∣3\vert A\vert^3

Choose the correct answer from the options given below:

Solution

✅ Correct Option: 2

For order 33, ∣adjA∣=∣A∣2|adjA|=|A|^{2} (III).

Since A⋅adjA=∣A∣IA\cdot adjA=|A|I, its determinant is ∣A∣3|A|^3 (IV).

∣A−1∣=∣A∣−1|A^{-1}|=|A|^{-1} (I).

Finally ∣A−1⋅adjA∣=∣A∣−1⋅∣A∣2=∣A∣|A^{-1}\cdot adjA|=|A|^{-1}\cdot|A|^{2}=|A| (II).

Keyboard Shortcuts

  • Left arrow: Previous question
  • Right arrow: Next question
  • S key: Jump to solution
  • Q key: Jump to question