Question

1. Let f(x) = 2x^+x-3 and g(x) = x-1 preform the indicated operation, then find the domain.

(f-g)(x)

a. x^2 -4 ; domain: positive real numbers
b. 2x^2-4 ; domain: all real numbers
c. x^2-4 ; domain: all real numbers
d. 2x^2-2 ; domain all real numbers

2. Let f(x) = 2x^2 + x -3 and g(x) = x-1 preform the indicated operation, then find the domain.

a. 2x^3 - x^2 - 4x+3; domain: all real numbers
b. 2x^3 + x^2 - 3x ; domain: all real numbers
c. 2x^3 + x^2 + 4x-3 ; domain: negative real numbers
d. 2x^2+x-3x+3


3. let f(c) = 2x^2 + x -3 and g(x) = x -1. Perfrom the indicated operation, then find the domain.

a. 1/2x+3; domain: all real numbers except x = -3/2
b. 2x+3; domain: all real numbers
c. 2x^2+3 domain: all real numbers
d. 2x+3; domain: all real numbers except x = 1

Answer 1

Explanation:

#1

• 
  `f(x) = 2x^2 + x - 3`
• 
  `g(x) = x - 1`

`\text{Find (f - g)(x):}`

• 
  `(f - g)(x) = f(x) - g(x) = 2x^2 + x - 3 - x + 1 = 2x^2 - 2`

Correct choice is D

• 
  `\text{The rest of the parts are confusing since f(x) and g(x) are same as in the first part}`