Problems

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A numeric set \(M\) containing 2003 distinct numbers is such that for every two distinct elements \(a, b\) in \(M\), the number \(a^2+ b\sqrt 2\) is rational. Prove that for any \(a\) in \(M\) the number \(q\sqrt 2\) is rational.

The numbers \(p\) and \(q\) are such that the parabolas \(y = - 2x^2\) and \(y = x^2 + px + q\) intersect at two points, bounding a certain figure.

Find the equation of the vertical line dividing the area of this figure in half.

For a given polynomial \(P (x)\) we describe a method that allows us to construct a polynomial \(R (x)\) that has the same roots as \(P (x)\), but all multiplicities of 1. Set \(Q (x) = (P(x), P'(x))\) and \(R (x) = P (x) Q^{-1} (x)\). Prove that

a) all the roots of the polynomial \(P (x)\) are the roots of \(R (x)\);

b) the polynomial \(R (x)\) has no multiple roots.

Let it be known that all the roots of some equation \(x^3 + px^2 + qx + r = 0\) are positive. What additional condition must be satisfied by its coefficients \(p, q\) and \(r\) in order for it to be possible to form a triangle from segments whose lengths are equal to these roots?