For what values of `aa n db ,` the system of equations `2x+a y+6z=8` `x+2y+b z=5` `x+y+3z=4` has: (i) a unique solution (ii) infinitely many solutions no solution

Explanation

`D=[[2, a, 6],
[1, 2, b],
[1 , 1 , 3]]`


`=(b-3)(a-2)`


`
D_{1}=
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