f(x) = x(to the second power) +3; g(x) = x - 7.

Which expression is equal to (f + g)(x)?

A. x ( to the second power) -4
B. x ( to the second power) -14x + 52
C. x ( to the second power) + x - 4
D. x ( to the third power) - 7x ( to the second power) + 3x - 21

Respuesta :

aachen

Given is function f(x) = x² + 3, and function g(x) = x - 7.

It says to perform the addition operation on functions such that (f+g)(x).

We can simply add the functions as follows :-

(f+g)(x) = f(x) + g(x)

(f+g)(x) = (x² + 3) + (x - 7)

(f+g)(x) = x² + 3 + x - 7

Arranging terms in decreasing order of their degree;

(f+g)(x) = x² + x + 3 - 7

Combining like terms;

(f+g)(x) = x² + x - 4

Hence, option C is correct i.e. (x² + x - 4).