Question

f(x)=4x+3

helpp

Answer 1

What are we helping to do?

Answer 2

figure out f(x)=4x+3

Answer 3

can you walk me through it

Answer 4

What do you mean figure it out? What are the instructions on the problem?

Answer 5

how do you do it

Answer 6

f(x) = 4x + 3 is a statement, not a question. What are you trying to do with the function?

Answer 7

get like an answer at the end what would i tell my teacher

Answer 8

what were you asked? there has to be some instructions

Answer 9

evaluate it

Answer 10

did they give you any other information?

Answer 11

like, did they give you an x value?

Answer 12

ok, now we're getting somewhere. Are you supposed to evaluate it at a specific value of x?

Answer 13

lets say x is 2

Answer 14

ok, so you would substitute 2 for x

f(x) = 4x + 3
f(2) = 4(2) + 3
then simplify that

Answer 15

Don't multiply f and 2 though, that's basically y. It stays f(2), or function of 2.

Answer 16

ok

Answer 17

11

Answer 18

yep

Answer 19

can i ask a couple more

Answer 20

ok

Answer 21

f(x)=2x+4
G(x)=X+1

Answer 22

no actually

Answer 23

f(x)=5x+3
G(x)=x+4

Answer 24

ok what are the instructions for this one?

Answer 25

i have to combine them but I'm confused

Answer 26

ok, there are lots of different ways to combine functions. It really depends on what you're asked for. Do you have a specific combination, or do you just want me to show you some

Answer 27

can you show me some

Answer 28

ok let's start with the basic 4

Adding
\(f(x) + g(x) = 5x + 3 + x + 4\)
\(= 6x + 7\)

Subtracting
\(f(x) - g(x) = 5x + 3 - (x + 4)\)
\(=5x+3-x-4\)
\(=4x-1\)

\(g(x) - f(x) = x + 4-(5x+3)\)
\(=x+4-5x-3\)
=\(-4x+1\)

Multiplying
\(f(x)\cdot g(x)=(5x+3)(x+4)\)
\(=5x^2+20x+3x+12\)
\(=5x^2+23x+12\)

Dividing
\[\frac{ f(x) }{ g(x) }=\frac{ 5x+3 }{ x+4 }\]
\[\frac{ g(x) }{ f(x) }=\frac{ x+4 }{ 5x+3 }\]

Answer 29

Then you can get more complex with something like
\(2f(x)-3g(x)=2(5x+3)-3(x+4)\)
=\(10x+6-3x-12\)
=\(7x-6\)

Answer 30

You can also compose functions, which is basically putting one inside the other.

To find f(g(x)) replace the x in f(x) with the function from g(x).
\(f(g(x))=5(x+4)+3\)
\(=5x+20+3\)
\(=5x+23\)

To find g(f(x)), do the opposite and replace the x in g(x) with f(x)
\(g(f(x))=(5x+3)+4\)
\(=5x+7\)

Answer 31

ok can you walk me through on
Subtracting
f(x)−g(x)=5x+3−(x+4)
=5x+3−x−4
=4x−1

g(x)−f(x)=x+4−(5x+3)
=x+4−5x−3
=−4x+1
how'd you get that

Answer 32

from the first line to the second you have to distribute.
-(x + 4) = -x - 4 for the first one
and -(5x + 3) = -5x - 3
then you combine like terms
Is that what you meant?

Answer 33

yea thank you and what about the others sorry I'm asking so much its just that i need to pass this

Answer 34

no problem. for multiplying you usually have to use FOIL or do some distribution.
dividing is just writing one on top of the other like a fraction

Answer 35

ok

Answer 36

Most of this is really knowing how to apply the distributive property and combine like terms

Answer 37

ok thank you

Answer 38

you're welcome