Answer:
4). [tex] x^{3} +5x+18 [/tex]
Step-by-step explanation:
The binomial (x+2) is a factor of [tex] x^{3} +5x+18. [/tex]
Since, (x + 2) is a factor.
So, x = - 2 is a root
Plug x = - 2 in [tex] x^{3} +5x+18 [/tex]
We find:
[tex] x^{3} +5x+18 [/tex]
[tex] =(-2)^{3} +5(-2)+18 [/tex]
[tex] =-8 - 10+18 [/tex]
[tex] = - 18+18 [/tex]
[tex] = 0 [/tex]
Since, at x = - 2 the value of the expression [tex] x^{3} +5x+18 [/tex] becomes zero.
Therefore, (x + 2) is a factor of [tex] x^{3} +5x+18 [/tex]
