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#### 2.7.49 Algebra Tutorial Exercise 2

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.