Which of the following quartic functions has x=-1 and x=-3 as its only two real zeros a. y=x^4-4x^3-4x^2-4x-3 b. y=-x^4-4x^3+4x^2+4x+3 c. y=x^4+4x^3+3x^2+4x-4 d. y=x^4+4x^3+4x^2+4x+3

option D

Step-by-step explanation:

x=-1 and x=-3 are the real zeros  

We plug in the x values in each equation and check which equation makes y=0

A) y=x^4-4x^3-4x^2-4x-3

x=-1 ,  

x=-3 ,

y is not equal to 0 so option A is not correct

B.y=-x^4-4x^3+4x^2+4x+3

x=-1 ,  

x=-3 ,

y is not equal to 0 so option B is not correct

C.y=x^4+4x^3+3x^2+4x-4

x=-1 ,  

x=-3 ,

y is not equal to 0 so option C is not correct

D) y=x^4+4x^3+4x^2+4x+3

x=-1 ,  

x=-3 ,

y=0 so option D has two real zeros x=-1  and x=-3

2

step-by-step explanation:

a

step-by-step explanation: