Which function has real zeros at x = 3 and x = 7?

f(x) = x2 + 4x – 21
f(x) = x2 – 4x – 21
f(x) = x2 – 10x + 21
f(x) = x2 – 10x – 21

Respuesta :

irspow
If it has real zeros at x=3 and 7, the factors of f(x) are:

(x-3)(x-7) so f(x) is

f(x)=x^2-10x+21

Answer:

Option 3 - [tex]f(x)=x^2-10x+21[/tex]

Step-by-step explanation:

To find : Which function has real zeros at x = 3 and x = 7?

Solution :

We have given the roots of the function i.e at x=3 and x=7

So, The factor form is (x-3) and (x-7).

Multiply both the roots to find the function,

[tex]f(x)=(x-3)(x-7)[/tex]

[tex]f(x)=x^2-7x-3x+21[/tex]

[tex]f(x)=x^2-10x+21[/tex]

Therefore, The required function is [tex]f(x)=x^2-10x+21[/tex]

So, option 3 is correct.

ACCESS MORE
ACCESS MORE
ACCESS MORE
ACCESS MORE