Question

Find f(g(x)) if f(x) = 2x + 1 and g(x) = x2 - 1.

Answer 1

Wherever you see an x in your function for f(x) replace it with the function of g(x). \[f(g(x)) = 2(x^2-2)+1\]

Answer 2

did u understood?

Answer 3

\[2x^2-3\]
@Jhannybean

Answer 4

but that's not one of my choices.

Answer 5

What are your answer choices?

Answer 6

ok \[f(g(x))= 2(x ^{2}-1)+1\]

Answer 7

\[f(g(x))=2x ^{2}-2+1\]

Answer 8

2(x^2-1)+1 = 2x^2 -2 + 1 = 2x^2 - 1

Answer 9

Oh, I made a typo there.

Answer 10

The \(x^2-2\) should have been \(x^2-1\)

Answer 11

\[f(g(x))= 2x ^{2}-1\]

Answer 12

hope this helps :)

Answer 13

No harm in correcting me :)

Answer 14

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

Answer 15

So this one - Find g(f(x)) if f(x) = 2x - 3 and g(x) = x - 1.

Answer 16

Should be -

\[2x^2 + x -3\]

Answer 17

g)x)-1 = (2x-3)-1 = 2x-4

Answer 18

Find f(g(x)) if f(x) = 2x + 1 and g(x) = x2 - 1.

My answer options are -

2x -1

\[2x^2-1\]

\[2x^2 + 1\]

\[2x^3-1\]

Answer 19

So if it's f(g(x)), shouldn't it be something along the lines of - (x^2 - 1)(2x+1)?

Answer 20

We've done this one.

Answer 21

Just scroll up?

Answer 22

It's just 2x -1 ?

Answer 23

You're not multiplying anything actually, you're just substituting the function of g(x).

Answer 24

Wait what? I am very confused.

Answer 25

\[f(g(x))= f(x^2-1) = 2(x^2-1)+1 = 2x^2-2+1 =2x^2-1\]

Answer 26

Do you see it now, @sloppycanada ?

Answer 27

Kind of..

Answer 28

which part is confusing you?

Answer 29

Where the "x" in 2x-1 went.

Answer 30

It was replaced by g(x)

Answer 31

Okay, so in this - Find g(f(x)) if f(x) = 2x - 3 and g(x) = x - 1.


It'd just be 1(2x -3) - 1?

Answer 32

Not quite, \[g(f(x)) = g(2x-3)= (2x-3)-1 = 2x-4\]

Answer 33

Okay so again - Find (f – g)(x) if f(x) = 2x – 6 and g(x) = 3x + 8.

(2x -6) - (3x+ 8) = -x +2?

Answer 34

Somewhat, but a small math error. \[(f-g)(x) = f(x) - g(x) = (2x-6)-(3x+8) = -x-(8+6) = -x-14\]

Answer 35

You've got the idea though :D

Answer 36

Find (f + g)(x) if f(x) = 1/2x + 4 and g(x) = -x - 3.


(1/2x +4) + (-x-3) = -1/2 + 1

Answer 37

-1/2x* +1?

Answer 38

Yep

Answer 39

Find the zeros of -4x + 6