Q. Use the Fundamental Theorem of Algebra to find the number of complex roots of the polynomial, including any repeated roots. x4+20x−18____
Find Degree: Look at the polynomial x4+20x−18 and find the highest power of x.Degree of the polynomial: 4.
Fundamental Theorem of Algebra: According to the Fundamental Theorem of Algebra, a polynomial of degree n has exactly n complex roots.So, the polynomial x4+20x−18 has 4 complex roots.