Question

For f(x)=2x + 1 and g(x)=x^2 - 7 find (f+g) (x)
Answers are
x^2 + 2x -6
x^2 + 2x +8
2x^3 -6
2x^2 - 15

Answer 1

when you say for example:
\[f(x)=4x^2+3,~~~~~and~~~~~g(x)=x^2-x+3\]
then,\[\color{blue}{(f+g)(x)}=(4x^2+3)+(x^2-x+3)=4x^2+3+x^2-x+3=\color{blue}{5x^2-x+6}\]

Answer 2

your problem is similar, you are adding what both of the functions are equivalent to.

Answer 3

Tallan, what is not clear, ask if you have some questions.

Answer 4

Im currently trying to solve it, nothing is unclear yet.

Answer 5

wait ok I have a question now. Do they have to be in parantheses? the 2x+1 and everything else in order to work?

Answer 6

I will set it up for you, and you will calculate:

f(x)=2x + 1
g(x)=x^2 - 7

( f + g ) (x)

\\ \\

(2x+1) + (x^2-7).

Answer 7

see what I am doing?

Answer 8

yes! so the 7 is negative then correct?

Answer 9

what do you mean?

Answer 10

the x^2-7 the 7 would be a negative 7 in this equation right? Or is it a positive and were just subtracting from it?

Answer 11

you are leaving out some terms.
x^2-7 is just the g(x)

but if you mean that you will remove the parenthesis, and from having:
(2x+1) + (x^2-7).

you will get:
2x+1 + x^2-7

(none of the signs change)

Answer 12

ok,
So when I calculated it I got A which was x^2 + 2x - 6

Answer 13

tallan bec this time you have to add things
and its doesn't matter if you put parenthesis or not
but when you have to subtract then you have to be careful like we did last time :)

Answer 14

ohm, nvm you are correct it is A.

Answer 15

good work Tallan!

Answer 16

Thank you! :)

Answer 17

not a problem:)