ap calc ab help please !
http://prntscr.com/8o63v0
http://prntscr.com/8o640n

- tmagloire1

ap calc ab help please !
http://prntscr.com/8o63v0
http://prntscr.com/8o640n

- Stacey Warren - Expert brainly.com

Hey! We 've verified this expert answer for you, click below to unlock the details :)

- jamiebookeater

I got my questions answered at brainly.com in under 10 minutes. Go to brainly.com now for free help!

- anonymous

f' is the line of the slope of f

- anonymous

So on your first problem if you can find which line is positive when one is increasing and negative while the other is decreasing it's f'

- tmagloire1

How can I find that without an equation?

Looking for something else?

Not the answer you are looking for? Search for more explanations.

## More answers

- anonymous

You can look at how line A decreases on the interval -infinity to zero

- anonymous

and then you can see that line b is negative from -infinity to zero

- tmagloire1

This problem is so confusing omg. Okay so is line B decreasing from .4- -infinit?

- anonymous

Yeah something like that

- anonymous

Really you just eyeball where one is negative and see if the other line is decreasing, and if the other is positive one is increasing

- tmagloire1

I think line B is positive and increasing while line A is decreasing

- anonymous

|dw:1444085317486:dw| you can see that the straight line is the derivative because where its positive the arch is increasing and where its negative its decreasing

- anonymous

I'd just tell you the answer but I think its kinda important to understand. Give me a sec

- tmagloire1

ok thanks

- anonymous

Okay so I marked where line B is increasing / decreasing

##### 1 Attachment

- anonymous

You can see that line b is negative while a is decreasing

- anonymous

as well as positive while a is increasing

- tmagloire1

Yep so that would mean that it's f normal right

- anonymous

since the derivative is the line of the slope we know b is the derivative

- tmagloire1

Ohh ok

- anonymous

Do you get it? A is decreasing so the slope is negative, the slope of the line is the derivative. Look for the line that is negative while decreasing

- tmagloire1

Oh ok so you just find where it's decreasing and negative and if the slope is negative than it's the derivative

- anonymous

Yeah but it doesnt have to be decreasing AND negative, just decreasing.

- tmagloire1

oh ok i understand thanks for going through the work to help me with that one

- anonymous

Your next problem is about the definition of a derivative at a point which is defined by this http://archives.math.utk.edu/visual.calculus/2/definition.8/eq1.gif

- anonymous

Basically the number you want to find (the point) is a. So since you're finding 2, a is equal to 2.

- tmagloire1

So i would just try plugging them into the two definition of limit equations and see what comes out?

- anonymous

Not really your thing would look like (f(2+h) - f(2))/h

- anonymous

So for f(2+h) you plug (2+h) wherever you see x and f(2) where ever you see h for the 2nd part.

- tmagloire1

wait what 2nd part are you referring to

- anonymous

the - f(2)

- anonymous

Do you understand how to plug everything in?

- anonymous

You dont need to actually do it for this problem, but thats important because sometimes you do. Its kinda situational

- tmagloire1

im not sure i understand how to plug them in

- anonymous

Alright

- anonymous

So I have (f(2+h) - f(2))/h
My equation is x^2 + 3x + 1
f(2+h) would be (2+h)^2 + 3(2+h) + 1
f(2) would be 2^2 + 3(2) + 1
I now have ((2+h)^2 + 3(2+h) + 1 - 2^2 + 3(2) + 1)/h

- anonymous

actually more like ((2+h)^2 + 3(2+h) + 1 - (2)^2 + 3(2) + 1)/h

- anonymous

So then you just do algebra and simplify to get answers

- anonymous

But you can tell this one is c because c has x -> 2 as the limit instead of h -> 0

- tmagloire1

oh ok so you take ((2+h)^2 + 3(2+h) + 1 - (2)^2 + 3(2) + 1)/h and simplify to see if i get the other answers

- tmagloire1

@swagmaster47 how can you tell the other answers are correct or not

Looking for something else?

Not the answer you are looking for? Search for more explanations.