If A= and ƒ(x)=2x² – 4x + 5 then ƒ(A)=?

42

If │A│=3 and A^-1=then adj A=?

43

If A is an invertible matrix and A^-1 = then A=?

45

If A= then A² – 4A = ?

46

If A is a 2-rowed square matrix and │A│=6 then =?