The length 2 cos(2π/13) is a root of where a is the larger root of p(x) = x³ - ax²-x+a-1, q(x) = x² + x - 3. What center (a, b)

Question

The length 2 cos(2π/13) is a root of
where a is the larger root of
p(x) = x³ - ax²-x+a-1,
q(x) = x² + x - 3.
What center (a, b) should we use to solve the cubic? Note that the center is constructible using just
a straightedge and compass.

Kunduz · Accepted Answer

Click to see the answer