Question

Which of the following correctly describes the nature of each curve below as either f or f'?

a. The answer cannot be determined.
b. f: Curve B, f': Curve A
c. f': both Curve A and Curve B
d. f : Curve A, f ′: Curve B

Answer 1

@myininaya you helped me on the last one please help me again

Answer 2

Well, cure A is power 3 and B is power 2.

Answer 3

so derivatives have nothing to do with this? is that true @GreenCat

Answer 4

Derivatives? I didn't understand the question and was going to ask for clarification, but now this seems like calculus. I don't think I should be helping. i only learned to College Algebra. Sorry.

Answer 5

Well, it seems as if the asker is smarter than me.

Answer 6

@TuringTest @iambatman @eliassaab i am in desperate need of help

Answer 7

;-; I'm sorry bye.

Answer 8

@ganeshie8 @quickstudent @wio @emily0824 @TheSmartOne @YanaSidlinskiy @iambatman @iGreen @PRAETORIAN.10 @Abhisar @AnswerMyQuestions @AlexandervonHumboldt2 @ShadowLegendX @Directrix @FrozenGamer @Hero @JFraser @kohai @Lyrae @zenyu @xXLittleLionXx @CausticSyndicalist @myininaya @mathmate @Michele_Laino

Answer 9

:/ Sorry I don't know. Can't help.
@iambatman @ganeshie8 @wio @Directrix @mathmate @DanJS
Might be able to help :)

Answer 10

this cant be determined. :}

Answer 11

@familyguymath
Have you done derivatives yet?

Answer 12

Derivatives are rates of change of a function.

Answer 13

yes

Answer 14

right

Answer 15

When a function is at it's maximum or minimum, what is the value of the derivative?

Answer 16

i forgot

Answer 17

i just know basic pwr rule

Answer 18

What is the derivative of x^2

Answer 19

2x

Answer 20

Good, see the figure?

Answer 21

When f(x) is decreasing, is f'(x) positive or negative?

Answer 22

so what ur saying is that the answer is b

Answer 23

its increasing

Answer 24

I don't know, because I have not checked which is f and which is f'.
When f(x) is decreasing, it is the part to the left of the vertex. Is f'(x) positive or negative?

Answer 25

i know the answer isnt b

Answer 26

If you are distracted by the answer by guessing, you will have a hard time doing your next problem. I want you to get your answer by yourself, after having understood how it works. Do we understand each other?

Answer 27

There's the saying"
Give a man a fish, he will be fed for a day (or less)
Show him how to fish, he can be fed for life!
Not about to give you a fish.

Answer 28

no i just got that wrong before when i answered it but thats not what is important to me i want to know how to do this
i mean my logic in it was that the parabola was not the derivative and the other was

but then i realizied it wasnt

Answer 29

i understand that and i dont want an answer i want to go about learning how to do it

Answer 30

Good, let's continue with my example of f(x)=x^2.
Which part of the function is decreasing?

Answer 31

the lefthand side, prior to the vertex

Answer 32

intersection

Answer 33

Excellent!
Which part is increasing?

Answer 34

after the intersection

Answer 35

@mathmate to the rescue! :)

Answer 36

Perfect! Good job!
Now did you notice that f'(x) is negative on the left of the vertex, and is positive to the right of the intersection?

Answer 37

This is what f'(x) means, it shows the rate of change of f(x).
ok so far?

Answer 38

yes

Answer 39

So what is the rate of change at the vertex (a minimum), you can read that off from f'(x).

Answer 40

2x

Answer 41

well, at x=0, f'(x) crosses the x-axis, which means that f'(0)=0.
The important lesson to learn is that at the maximum or minimum of a function, f'(x)=0!

Answer 42

oh okay :)

Answer 43

This fact will help you in your problem to distinguish which one is f(x), and which one is f'(x).
Can you give it a try now?

Answer 44

not to intrude but like i said up there i think its A at least thats what i got when solving it.

Answer 45

yes

Answer 46

to mathmate doing it rn

Answer 47

@some.random.cool.kid
Thank you for trying to help. I am here to show him HOW to find it, not to give him the answer.

Answer 48

@some.random.cool.kid
I hope you would do the same, because at Openstudy, we are not to give answers only. We are expected to guide and explain.
You can read all about it at "code of conduct".

Answer 49

yeah i got that and im not giving him the answer im just saying from my perspective of what it seems like but carry on. im doing my own math segment so go ahead and continue so he can pass. :}

Answer 50

Exactly what I want him to do: pass but by himself.
Thank you for understanding.
@some.random.cool.kid

Answer 51

curve b looks like a parabola of x^2 whereas curve a looks like its x^to an odd number

Answer 52

Good, you see the difference.
Another way to do that is if you can tell the degree of the curves, you can judge from the power rule: the degree of f'(x) of a polynomial is always on less than that of f(x).
But I want to show you another check.

Answer 53

Yes, curve B is a 2nd degree, and curve A is a 3rd degree.
That tells you that ....

Answer 54

@familyguymath
still there?

Answer 55

answer cannot be determined due to the fact that neither of each other is another's derivative, right?

Answer 56

Can you not deduce something (using the power rule) from
curve B is second degree, and curve A is third degree?

Answer 57

Also you can confirm that the value of f'(x)=0 when f(x) has a maximum or minimum.
(A) is not the answer, for your information.

Answer 58

x^2 derivative is 2x and x^3 derivative is 3x^2

Answer 59

????

Answer 60

@mathmate

Answer 61

So which one is f(x) and which one is f'(x)?
We still have to check/confirm after we have decided!

Answer 62

f is curve a and f' is curve b

Answer 63

Perfect! Now we need to do some check!