Question

Four polynomial functions are shown below:

f(x) = x3 + 3x2 - 4x - 12
g(x) = x3 - 3x - 2
p(x) = x2 + 3x + 2
t(x) = x2 + x - 2

Which of the following functions has -1 and -2 as its zeros?

f(x)

g(x)

p(x)

t(x)

Answer 1

you can plug in -1 and -2 into each of the function too see in which function will both x=-1 and x=-2 result in f(x)=0.

OR, you can solve each one.

What do you prefer?

Answer 2

well for starters since it's 2 zeros then it has to be p(x) or t(x)
so
p(x)= x²+3x+2 = (x+1) (x+2)
t(x)= x²+x-2 = (x-1) (x+2)

so the answer is p(x) because x+1= 0 x=-1 and x+2 = 0 x=-2

Answer 3

p(x)