12-3 Find the inverse of the matrix
A=[[1,1,1],[1,2,3],[1,4,9]]
by using the formula A^(-1)=(1)/(detA)AdjA (see Section 12.2).
12-4 Let A be an invertible matrix. Show that det(A^(-1))=(1)/(detA).
HinT: Apply det to both sides of the equation AA^(-1)=I.
12-3Find the inverse of the matrix
A=
by using the formula A
-
Adj A (see Section 12.2). det A
12-4 Let A be an invertible matrix. Show that det(A-1) = 1/(det A)
HINT: Apply det to both sides of the equation AA-1 = I.