Question

Let $α_1,α_2,….,α_7$ be the roots of the equation $𝑥^7+3𝑥^5−13𝑥^3−15𝑥=0$ and $|α_1|≥|α_2|≥⋯≥ |α_7|$. Then $α_1α_2−α_3α_4+α_5α_6$ is equal to ____.

Answer 1

The answer is 3.