In: Math
Does every polynomial equation have at least one real root?
a. Why must every polynomial equation of degree 3 have at least one real root?
b. Provide an example of a polynomial of degree 3 with three real roots. How did you find this?
c. Provide an example of a polynomial of degree 3 with only one real root. How did you find this?
No, every polynomial need not have a real root.
(a) Yes,any polynomial of degree 3 must have at least one real root. Since complex roots appear in pair, thus, any polynomial of degree 3 can have either 2 complex roots or zero complex roots. Thus, it must have at least one real root.
(b) is a polynomial with three real roots. We choose all the roots in real.
(c) is a polynomial with one real and two complex roots since has no real roots