# Thread: Algebra III/trig 2 problems

1. ## Algebra III/trig 2 problems

I need help on these two problems my teacher gave us. I'm already failing the class but I need at least one good grade. Directions: A) f+g(x)
B) f-g(x) C) fg(x) D) F/g(x) Find the domain

1. f(x)=2x-5 g(x)=2-x
A=
B=
C=
D=

2. f(x)=2x-5 g(x)=4

2. Originally Posted by hatemath101
I need help on these two problems my teacher gave us. I'm already failing the class but I need at least one good grade. Directions: A) f+g(x)
B) f-g(x) C) fg(x) D) F/g(x) Find the domain

1. f(x)=2x-5 g(x)=2-x
A=
B=
C=
D=

2. f(x)=2x-5 g(x)=4
$\displaystyle (f + g)(x) = f(x) + g(x)$

$\displaystyle (f - g)(x) = f(x) - g(x)$

$\displaystyle fg(x) = f(x)g(x)$

$\displaystyle \frac fg(x) = \frac {f(x)}{g(x)}$

we are dealing with polynomials here, so the domains for A, B, and C are all real x, that is $\displaystyle x \in (- \infty, \infty)$

for D, obviously the denominator cannot be zero, so the domain is all real x such that $\displaystyle g(x) \ne 0$