NCERT Exercise 4.3 Q2 - Determinants
Question: Write minors and cofactors of (i) |[[1,0,0],[0,1,0],[0,0,1]]| and (ii) |[[1,0,4],[3,5,-1],[0,1,2]]|.
Answer: (i) Diagonal minors and cofactors are 1; all others 0. (ii) M11=11, M12=6, M13=3, M21=-4, M22=2, M23=1, M31=-20, M32=-13, M33=5; A11=11, A12=-6, A13=3, A21=4, A22=2, A23=-1, A31=-20, A32=13, A33=5.
Full step-by-step NCERT solution with diagrams on Something by Zero.