Consider f(x) = 2x2 + 1 and g(x) = 3x − 6. Which statement about f + g is true?
A. It is a linear function.
B. It is a quadratic function.
C. The domain is x ≥ −3.
D. The range is all real numbers.

Respuesta :

Given:

The two functions are:

[tex]f(x)=2x^2+1[/tex]

[tex]g(x)=3x-6[/tex]

To find:

The correct statement about the function [tex]f+g[/tex].

Solution:

We have,

[tex]f(x)=2x^2+1[/tex]

[tex]g(x)=3x-6[/tex]

Adding both functions, we get

[tex]f+g=f(x)+g(x)[/tex]

[tex]f+g=2x^2+1+3x-6[/tex]

[tex]f+g=2x^2+3x-5[/tex]

It is a quadratic function. So, option A is incorrect and option B is correct.

The domain of [tex]f+g[/tex] is all real numbers because it is defined for all real values of x. So, option C is incorrect.

The range of [tex]f+g[/tex] cannot be the all real numbers because it has a minimum value of y as the leading coefficient is positive. So, option D is incorrect.

Therefore, the correct option is B.