Question

x3+2x-1 find complex roots

Answer 1

there is a big retarded formula for \(\large\color{slate}{ ax^3+bx-c }\), I don't remember it and don't use it though.

Answer 2

the real root, is given by the subsequent formula:
\[x=\sqrt[3]{q+\sqrt{q ^{2}-p ^{3}}}+\sqrt[3]{q-\sqrt{q ^{2}-p ^{3}}}\]
wherep=-2/3, and q=1/2

Answer 3

http://www.sosmath.com/algebra/factor/fac11/fac11.html