Question

Find (f+g),(f-g)(x), (f*g)(x), and (f/g)(x) and g(x) .
f(x)=2x+1
g(x)=x-3

Answer 1

do you want the process or just answers?

Answer 2

process please (:

Answer 3

Sure, it's all just about substituting and simplifying. Here's the first one for free just as an example:
\[f(x)=2x+1\]\[g(x)=x-3\]\[(f+g)(x)=f(x)+g(x)=(2x+1)+(x-3)=3x-2\]all we did is just perform the operation (in this case addition) on each function and treated them like regular polynomials.
So what do you think we will do for\[ (f-g)(x)\]????

Answer 4

the same thing?

Answer 5

but subtracting

Answer 6

exactly, can you try it and show your work? just so I know what you need help with.

Answer 7

(x-3)-(2x+1)

Answer 8

= 2x^2-7x-3?

Answer 9

for the first one you had it set up right for g-f, but you want f-g. You also didn't simplify, please do that over.
The next one is correct. :)

Answer 10

(2x+1)-(x-3)

Answer 11

simplify...

Answer 12

how?

Answer 13

(2x+1)-(x-3)=2x+1-x+3=x+4
do you not follow that?
you seemed to have no trouble multiplying the two expressions, but you can't subtract them?
I think you are over-thinking this problem :)

Answer 14

so what about the last one? f/g
can it be simplified?

Answer 15

i got that one, its 3x/-2

Answer 16

no, not quite...\[{f(x)\over g(x)}={2x+1\over x-3}\]it is a direct substitution and cannot be simplified.

I think you need to work on combining like terms and simplification, you seemed to have missed some important things. I'm sure you'll get it of you keep trying.
Good luck!