How do you write a possible quadratic equation in standard form that has the given roots {1+or-i}?

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Answer 1 · 2018-03-29T06:09:08

The possible cubic equation happens to be:

$x^3-x^2+x-1=0$

roots are
$x=1$

$x-1=0$

$x=-i$

$x+i=0$

Complex numbers occur always in conjugates

$x=i$ ,
$x-i=0$

$x=-i$ ,
$x+i=0$

Hence, the factors are:

$(x-1), (x-i), (x+i)$

$(x-1)(x-i)(x+i)=0$

$(x-1)(x^2+1)=0$

The possible cubic equation happens to be:

$x^3-x^2+x-1=0$