Question

question #7 determine which of the following numbers is not a root of f(x)=x^4 - 3x^3 - 11x^2 + 3x + 10. 2 1 5 -1

Explanation:

Step1: Substitute x = 2

$f(2)=2^{4}-3\times2^{3}-11\times2^{2}+3\times2 + 10=16-24 - 44+6 + 10=-36$

Step2: Substitute x = 1

$f(1)=1^{4}-3\times1^{3}-11\times1^{2}+3\times1 + 10=1-3-11 + 3+10=0$

Step3: Substitute x = 5

$f(5)=5^{4}-3\times5^{3}-11\times5^{2}+3\times5 + 10=625-375-275 + 15+10=0$

Step4: Substitute x=-1

$f(-1)=(-1)^{4}-3\times(-1)^{3}-11\times(-1)^{2}+3\times(-1)+10=1 + 3-11-3 + 10=0$

Answer:

2