The answer is probably (c).
Answer:
A factor of f(x) is (x + 1).
Step-by-step explanation:
When we put x+1= 0 then we get the value x= -1
This value is then put into the function to find out whether it is a root or not. For a root to exist it must not have a remainder or the remainder must be zero.
Suppose the function is
F(x)= 2x³ - 42x - 40
f(-1)= 2(-1)³ - 42(-1) - 40
f(-1)= -2 + 42- 40
f(-1)= 0
This gives -1 as the root of the function.