Question

A quartic polynomial P(x) has rational coefficients. If 2 − i and-√5 are roots of P(x) = 0, what are the other 2 roots?

Answer 1

2 + i and + √5

Explanation:

Since P(x) is a quartic equation, it has 4 roots.

Since 2 - i and -√5 are two of its roots, then its conjugate pairs of 2 + i and + √5 are its other two roots.

So, its other two roots are 2 + i and + √5