(1) `x^3 - 3x^2 - 6x + 8`
Here `p(x)=x^3 - 3x^2 - 6x + 8`
sum of coefficient of all the terms of `p(x) = 1 - 3 - 6 + 8 = 0`
`:.` `(x-1)` is a factor of `p(x)`.
Now, `p(x) = x^3 - 3x^2 - 6x + 8`
`=x^3 - x^2 - 2x^2 + 2x - 8x + 8`
`=x^2(x - 1) - 2x(x - 1) - 8(x - 1)`
`=(x - 1)(x^2 - 2x - 8)`
`=(x - 1)(x - 4)(x + 2)`

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