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If A[{:(2,4,4),(2,5,4),(2,5,3):}], then ...

If `A[{:(2,4,4),(2,5,4),(2,5,3):}]`, then verify that A adjA = |A|l. Also find `A^(-1)`.

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`A[{:(2,4,4),(2,5,4),(2,5,3):}]|A|=2(15-20)-4(6-8)+4(10-10)`
`=-10+8+0`
`=-2`
Now, `{:(A_11=-5,|,A_21=8,|,A_31=-4),(A_12=2,|,A_22=-2,|,A_32=0),(A_13=0,|,A_23=-2,|,A_33=2):}`
adj `A={:(-5,8,-4),(2,-2,0),(0,2,2):}]`
Now, A adj `A=[{:(2,4,4),(2,5,4),(2,5,3):}][{:(-5,8,-4),(2,-2,0),(0,2,2):}]=[{:(-2,0,0),(0,-2,0),(0,0,2):}]=-2[{:(1,0,0),(0,1,0),(0,0,1):}]`
`=-2*l`
`=|A|*l`
Now find `A^(-1)`
`=1/-2[{:(-5,8,-4),(2,-2,0),(0,2,2):}]=[{:(5/2,-4,2),(-1,1,0),(0,-1,-1):}]`
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