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Suppose our roots are ‘`[a, b, c]`’. We want a polynomial which
is zero when ‘`x`’ is any of these values. The trivial polynomial
‘`x-a`’ is zero when ‘`x=a`’, so the product ‘`(x-a)(x-b)(x-c)`’
will do the job. We can use `a c x` to write this in a more
familiar form.

```
1: 34 x - 24 x^3 1: [1.19023, -1.19023, 0]
. .
r 2 a P x RET
```

```
1: [x - 1.19023, x + 1.19023, x] 1: x*(x + 1.19023) (x - 1.19023)
. .
V M ' x-$ RET V R *
```

```
1: x^3 - 1.41666 x 1: 34 x - 24 x^3
. .
a c x RET 24 n * a x
```

Sure enough, our answer (multiplied by a suitable constant) is the same as the original polynomial.