### 5.34.3 Exact bounds for real roots of a polynomial: VAS

The VAS command takes one argument, a polynomial.
VAS returns a list of intervals which contain the real roots of the polynomial using the Vincent-Akritas-Strzebonski algorithm. Each interval will contain exactly one root.
Input:

VAS(x^3 - 7*x + 7)

Output:

[[-4,0],[1,3/2],[3/2,2]]

Input:

VAS(x^5 + 2*x^4 - 6*x^3 - 7*x^2 + 7*x + 7)

Output:

[[-5,-1],-1,[1,3/2],[3/2,2]]

Input:

VAS(x^3 - x^2 -2*x + 2)

Output:

[[-3,0],1,[1,3]]