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Given that matrix `A[(x,3,2),(1,y,4),(2,2,z)]`. If `xyz=60` and `8x+4y+3z=20`, then A(adj A) is equal toA. `[(64,0,0),(0,64,0),(0,0,64)]`B. `[(88,0,0),(0,88,0),(0,0,88)]`C. `[(68,0,0),(0,68,0),(0,0,68)]`D. `[(34,0,0),(0,34,0),(0,0,34)]`

Answer» Correct Answer - C
A adj. `A=|A| I`
`|A|=xyz-8x-3(z-8)+2(2-2y)`
`|A|=xyz-(8x+3z+4y)+28`
`=60-20+28=68`
`implies` A(adj. A)`=68 [(1,0,0),(0,1,0),(0,0,1)]=[(68,0,0),(0,68,0),(0,0,68)]`


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