Numeric roots of a polynomial

The proot command numerically finds the roots of a squarefree polynomial.

proot takes P, a squarefree polynomial, either in symbolic form or as a list of polynomial coefficients (written by decreasing order).
proot(P) returns a list of the numeric roots of P.

Find the numeric roots of P(x)=x³+1.

proot([1,0,0,1])

or:

proot(x^3+1)

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−1.0,0.5−0.866025403784 i,0.5+0.866025403784 i

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Find the numeric roots of x²−3.

proot([1,0,-3])

or:

proot(x^2-3)

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−1.73205080757,1.73205080757

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