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## #1 2021-06-04 04:43:47

nycmathguy
Member
Registered: 2021-06-02
Posts: 53

### Investigate Limit For Piecewise Function

Use a graph to investigate the limit of f(x) as x tends to c at the given c number.

Let c = 2

Top portion of piecewice function: x + 2 if x < 2
Middle portion of piecewise function: 4 if x = 2
Bottom portion of piecewise function: x^2 if x > 2

Note: f(x) is a three-part function.

Solution:

Find the limit of (x + 2) as x tends to 2 from the left side.

(2 + 2) = 4

Find the limit of x^2 as x tends to 2 from the right side.

(2)^2 = 4

LHL = RHL

Thus, the limit of f(x) as x tends to 2 is 4.

Is this right?

Note: Sorry that I could not upload a picture for clarity. Still waiting for step 2 for uploading pictures and graphs.

P. S. I don't have a computer or laptop. All this typing work is done on my cell phone. This is true.

Last edited by nycmathguy (2021-06-06 05:24:54)

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## #2 2021-06-04 05:42:13

Bob
Registered: 2010-06-20
Posts: 9,207

### Re: Investigate Limit For Piecewise Function

As the function has 3 parts I would have included that y = 4 there too, but I'm probably being very picky.  What you have said is excellent.

Picture step 2. Do you have a picture that you want to appear on the forum using imgur?

On my laptop I can do a  screen shot and then edit and save the resulting image.  Let's try any image to start with.  We can look at how you edit a shot later.

The app should have an option to upload the image to your account.  Let me know if you have been able to do that.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

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## #3 2021-06-04 08:19:00

nycmathguy
Member
Registered: 2021-06-02
Posts: 53

### Re: Investigate Limit For Piecewise Function

Bob wrote:

As the function has 3 parts I would have included that y = 4 there too, but I'm probably being very picky.  What you have said is excellent.

Picture step 2. Do you have a picture that you want to appear on the forum using imgur?

On my laptop I can do a  screen shot and then edit and save the resulting image.  Let's try any image to start with.  We can look at how you edit a shot later.

The app should have an option to upload the image to your account.  Let me know if you have been able to do that.

Bob

I don't have any particular picture in mind to upload. However, I will take a picture of this piecewise function as step 2.

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## #4 2021-06-04 08:28:22

nycmathguy
Member
Registered: 2021-06-02
Posts: 53

### Re: Investigate Limit For Piecewise Function

Bob wrote:

As the function has 3 parts I would have included that y = 4 there too, but I'm probably being very picky.  What you have said is excellent.

Picture step 2. Do you have a picture that you want to appear on the forum using imgur?

On my laptop I can do a  screen shot and then edit and save the resulting image.  Let's try any image to start with.  We can look at how you edit a shot later.

The app should have an option to upload the image to your account.  Let me know if you have been able to do that.

Bob

I took a picture of the piecewise function for this thread. Image has been posted to the app. What's next?

Last edited by nycmathguy (2021-06-04 08:37:53)

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## #5 2021-06-05 20:18:19

Bob
Registered: 2010-06-20
Posts: 9,207

### Re: Investigate Limit For Piecewise Function

hi nycmathguy,

When I use Imgur I use a browser connection on my laptop.  I don't know how different the app is but somewhere there should be a set of options like this:

This is the forum friendly BCCode link so the forum's software knows where to find the image to imbed in your post.

So you copy the BCCode line (I've ticked the one you want) into your post and when you submit it the picture should appear in your post.

Let me know how you get on.  If your next post has an image, I'll know you've 'cracked it'.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

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## #6 2021-06-06 05:01:38

nycmathguy
Member
Registered: 2021-06-02
Posts: 53

### Re: Investigate Limit For Piecewise Function

Bob wrote:

hi nycmathguy,

When I use Imgur I use a browser connection on my laptop.  I don't know how different the app is but somewhere there should be a set of options like this:

https://i.imgur.com/Y8hTnmK.gif

This is the forum friendly BCCode link so the forum's software knows where to find the image to imbed in your post.

So you copy the BCCode line (I've ticked the one you want) into your post and when you submit it the picture should appear in your post.

Let me know how you get on.  If your next post has an image, I'll know you've 'cracked it'.

Bob

I will go back to the app now and try again. We are almost there.

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## #7 2021-06-06 05:30:17

nycmathguy
Member
Registered: 2021-06-02
Posts: 53

### Re: Investigate Limit For Piecewise Function

Bob wrote:

hi nycmathguy,

When I use Imgur I use a browser connection on my laptop.  I don't know how different the app is but somewhere there should be a set of options like this:

This is the forum friendly BCCode link so the forum's software knows where to find the image to imbed in your post.

So you copy the BCCode line (I've ticked the one you want) into your post and when you submit it the picture should appear in your post.

Let me know how you get on.  If your next post has an image, I'll know you've 'cracked it'.

Bob

Here is the link of the attachment:

http://imgur.com/gallery/4l3aenO

No image has been displayed.

I'm just not getting this stuff. I am not too savvy in terms of technical stuff.
I have a better idea. If you are truly interested in helping me with calculus, here are two best options:

OR

2. If you are on FB, I can easily create a Calculus Group. We could interact the way as well.

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## #8 2021-06-06 19:47:47

Bob
Registered: 2010-06-20
Posts: 9,207

### Re: Investigate Limit For Piecewise Function

Nearly there.  Look again at the list of imgur options.  The one you need to choose is called BCCode message boards and forums and has the link inside img tags.  Try that and hopefully it will work.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

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## #9 2021-06-07 05:59:33

nycmathguy
Member
Registered: 2021-06-02
Posts: 53

### Re: Investigate Limit For Piecewise Function

Bob wrote:

Nearly there.  Look again at the list of imgur options.  The one you need to choose is called BCCode message boards and forums and has the link inside img tags.  Try that and hopefully it will work.

Bob

I will try one more time later this evening.

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## #10 2021-06-07 09:40:03

nycmathguy
Member
Registered: 2021-06-02
Posts: 53

### Re: Investigate Limit For Piecewise Function

nycmathguy wrote:
Bob wrote:

hi nycmathguy,

When I use Imgur I use a browser connection on my laptop.  I don't know how different the app is but somewhere there should be a set of options like this:

https://i.imgur.com/Y8hTnmK.gif

This is the forum friendly BCCode link so the forum's software knows where to find the image to imbed in your post.

So you copy the BCCode line (I've ticked the one you want) into your post and when you submit it the picture should appear in your post.

Let me know how you get on.  If your next post has an image, I'll know you've 'cracked it'.

Bob

I will go back to the app now and try again. We are almost there.

There is no set of options in the app. Should I edit my original thread and click BCCode?

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## #11 2021-06-07 19:41:05

Bob
Registered: 2010-06-20
Posts: 9,207

### Re: Investigate Limit For Piecewise Function

hi nycmathguy

I've spent some time trying to sort this out.  I can insert a link to one of my images into your post and that works.  I've tried modifying your link so that it is identical to mine (replacing my link with gallery/4l3aenO) but that gets a forum software error.

So I've downloaded the imgur app and signed in.  I couldn't find a way to get the BCCode so I searched through the FAQs for the app and found that the phone app doesn't have this feature.  So, at the moment, imgur isn't the solution.  Sorry to have misled you but I have only ever tried the phone app today.

There must be an alternative app that will work.  I'll go searching and let you know if I can find anything.

If I copy and paste your link into the address bar of my browser I can get your image so I have been able to view it but not embedded into a post.

A workaround would be to log in to imgur at an internet cafe.  Have to be a good image though, as it'll cost you the price of a coffee

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

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## #12 2021-06-07 20:41:32

Bob
Registered: 2010-06-20
Posts: 9,207

### Re: Investigate Limit For Piecewise Function

Question: i phone or Android?

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

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## #13 2021-06-08 12:25:16

nycmathguy
Member
Registered: 2021-06-02
Posts: 53

### Re: Investigate Limit For Piecewise Function

Bob wrote:

hi nycmathguy

I've spent some time trying to sort this out.  I can insert a link to one of my images into your post and that works.  I've tried modifying your link so that it is identical to mine (replacing my link with gallery/4l3aenO) but that gets a forum software error.

So I've downloaded the imgur app and signed in.  I couldn't find a way to get the BCCode so I searched through the FAQs for the app and found that the phone app doesn't have this feature.  So, at the moment, imgur isn't the solution.  Sorry to have misled you but I have only ever tried the phone app today.

There must be an alternative app that will work.  I'll go searching and let you know if I can find anything.

If I copy and paste your link into the address bar of my browser I can get your image so I have been able to view it but not embedded into a post.

A workaround would be to log in to imgur at an internet cafe.  Have to be a good image though, as it'll cost you the price of a coffee

Bob

Hey brother, don't worry about it. In terms of the cafe, this does not work for me. No internet cafe nearby. I wouldn't go there anyway. Not my style, not my thing to do.
My solution is the easiest.

2. Search for me on FB. I can create a Calculus Private Group where my questions with pictures would be posted.

3. My phone is android. A-21 Samsung.

Last edited by nycmathguy (2021-06-08 12:25:27)

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## #14 2021-06-08 12:26:39

nycmathguy
Member
Registered: 2021-06-02
Posts: 53

### Re: Investigate Limit For Piecewise Function

Bob wrote:

Question: i phone or Android?

Bob

Android.

Samsung A-21.

Last edited by nycmathguy (2021-06-09 09:48:38)

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## #15 2021-06-08 19:47:40

Bob
Registered: 2010-06-20
Posts: 9,207

### Re: Investigate Limit For Piecewise Function

Android is perfect.  Photobucket offers a similar service to imgur and does enable BBCode for android operating systems.  So the Photobucket app should allow you do insert images into your posts.  I'll try it myself later today.

later edit:  I've spent an hour chasing around the photobucket site trying to get the BBCode.  Why don't companies have a manual these days? Eventually found the link but it's greyed out.  More chasing around to find out why.  Finally got to a screen that says I've got to pay up to get this feature.  Really?  I really object to having my time wasted like this.  They said it was a feature, and it may be, but they 'forgot' to say that the free app doesn't do it.  Once again I'm so sorry.

Back to the drawing board.  Anyone else on MIF found a way to do this on a mobile?

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

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## #16 2021-06-09 09:48:22

nycmathguy
Member
Registered: 2021-06-02
Posts: 53

### Re: Investigate Limit For Piecewise Function

Bob wrote:

Android is perfect.  Photobucket offers a similar service to imgur and does enable BBCode for android operating systems.  So the Photobucket app should allow you do insert images into your posts.  I'll try it myself later today.

later edit:  I've spent an hour chasing around the photobucket site trying to get the BBCode.  Why don't companies have a manual these days? Eventually found the link but it's greyed out.  More chasing around to find out why.  Finally got to a screen that says I've got to pay up to get this feature.  Really?  I really object to having my time wasted like this.  They said it was a feature, and it may be, but they 'forgot' to say that the free app doesn't do it.  Once again I'm so sorry.

Back to the drawing board.  Anyone else on MIF found a way to do this on a mobile?

Bob

I understand what you're saying.

My question again is:

Why not simply communicate via email?

I can create a calculus file for me to keep my questions and your replies for extra study and practice. I can take a picture of the graph or geometric figure and attach it to the email for you to see. Why is this not a good idea?

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## #17 2021-06-09 20:24:24

Bob
Registered: 2010-06-20
Posts: 9,207

### Re: Investigate Limit For Piecewise Function

If you do what you did the other day using imgur then I can see your diagrams quite satisfactorily.  They just don't appear embedded in the post.

Let's start on some maths.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

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## #18 2021-06-10 02:35:02

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 4,685

### Re: Investigate Limit For Piecewise Function

I don't have a smartphone and don't know much about them, but anyway, here's something that may help re this image problem...

I was able to view the image on my PC via the link from post #7. However, I suspect that the link isn't to the image itself, because Imgur image urls begin with 'https://i.imgur.com/' (different from nyc's 'http://imgur.com/gallery/'), and include a file extension (eg, '.jpg') after the filename (which nyc's doesn't).

That could account for the image not displaying here.

When I right-click the image in Imgur and select 'Copy image address', like so...

...I'm given the url 'https://i.imgur.com/ZVsL4f8.jpg', which agrees with the starting format I mentioned above.

Entering that url between img tags successfully displays the image:

However, that image size is way too large for forum viewing (well, on my PC it is), so I shrank it to 640x480 for comparison:

The shrunk size fills just over half the width of my screen, which is about right for me.

"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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## #19 2021-06-10 10:54:27

nycmathguy
Member
Registered: 2021-06-02
Posts: 53

### Re: Investigate Limit For Piecewise Function

phrontister wrote:

I don't have a smartphone and don't know much about them, but anyway, here's something that may help re this image problem...

I was able to view the image on my PC via the link from post #7. However, I suspect that the link isn't to the image itself, because Imgur image urls begin with 'https://i.imgur.com/' (different from nyc's 'http://imgur.com/gallery/'), and include a file extension (eg, '.jpg') after the filename (which nyc's doesn't).

That could account for the image not displaying here.

When I right-click the image in Imgur and select 'Copy image address', like so...

...I'm given the url 'https://i.imgur.com/ZVsL4f8.jpg', which agrees with the starting format I mentioned above.

Entering that url between img tags successfully displays the image:

However, that image size is way too large for forum viewing (well, on my PC it is), so I shrank it to 640x480 for comparison:

The shrunk size fills just over half the width of my screen, which is about right for me.

Can you provide the steps? What exactly must I do here?

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## #20 2021-06-10 12:31:14

nycmathguy
Member
Registered: 2021-06-02
Posts: 53

### Re: Investigate Limit For Piecewise Function

phrontister wrote:

I don't have a smartphone and don't know much about them, but anyway, here's something that may help re this image problem...

I was able to view the image on my PC via the link from post #7. However, I suspect that the link isn't to the image itself, because Imgur image urls begin with 'https://i.imgur.com/' (different from nyc's 'http://imgur.com/gallery/'), and include a file extension (eg, '.jpg') after the filename (which nyc's doesn't).

That could account for the image not displaying here.

When I right-click the image in Imgur and select 'Copy image address', like so...

...I'm given the url 'https://i.imgur.com/ZVsL4f8.jpg', which agrees with the starting format I mentioned above.

Entering that url between img tags successfully displays the image:

However, that image size is way too large for forum viewing (well, on my PC it is), so I shrank it to 640x480 for comparison:

The shrunk size fills just over half the width of my screen, which is about right for me.

What do you mean by "Entering that url between img tags successfully displays the image:"?

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## #21 2021-06-10 12:33:42

nycmathguy
Member
Registered: 2021-06-02
Posts: 53

### Re: Investigate Limit For Piecewise Function

Bob wrote:

If you do what you did the other day using imgur then I can see your diagrams quite satisfactorily.  They just don't appear embedded in the post.

Let's start on some maths.

Bob

I will copy and paste the link that shows the image. You can then copy and paste the link in your url to see the picture.

Moving on....

Back to limits.

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## #22 2021-06-10 12:46:39

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 4,685

### Re: Investigate Limit For Piecewise Function

nycmathguy wrote:

Can you provide the steps? What exactly must I do here?

phrontister wrote:

I don't have a smartphone and don't know much about them, but anyway, here's something that may help re this image problem...

Sorry that my info wasn't helpful, but I can't provide the steps, nor advise what you must do.

"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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## #23 2021-06-10 15:26:00

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 4,685

### Re: Investigate Limit For Piecewise Function

nycmathguy wrote:

What do you mean by "Entering that url between img tags successfully displays the image:"?

Copy the url by right-clicking (or whatever you do on a 'smart'phone) on your Imgur image, and select 'Copy image address' (ie, the 'url'). When I did that on my PC, the copied url was 'https://i.imgur.com/ZVsL4f8.jpg'.

Then paste the url between 'img' (image) tags, to look like this:

``[img]https://i.imgur.com/ZVsL4f8.jpg[/img]``

Enter the result into your post, and the image should display. It does for me.

If the image display is too large (original size is 4608x3456 px, which is HUGE), refer to my post #18.

I get the following display sizes with your 4608x3456 px image:
(a) when not in a 'hide' box: across the width of the forum screen.
(b) when in a 'hide' box: nearly 4 times the width of the computer screen.

If you want to hide your image in a 'hide' box, enter the url as follows (but without the commas in the 'hide' brackets):

``[hide,][img]https://i.imgur.com/ZVsL4f8.jpg[/img][/hide,]``

Note: I entered the commas to render the 'hide' action inactive, otherwise a 'hide' box (containing the 'img' code) would have appeared instead of the 'hide' tags.

The 'img' tags are missing from your quotes of my post #18, which explains why the images don't show when I click on the links in your post.

So, it looks like 'img' tags vanish when quoting another post, which I'm pretty sure wasn't the case before the recent server change. And they vanish whether they're in a 'hide' box or not...but the 'hide' tags remain.

Last edited by phrontister (2021-06-10 17:30:52)

"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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## #24 2021-06-10 20:13:23

Bob
Registered: 2010-06-20
Posts: 9,207

### Re: Investigate Limit For Piecewise Function

I tried adding the 'i' in i.imgur to the link but got a server error.  I also tried putting one of my links into the post and that worked.  So I changed the imgur identifying code and it failed.  I conclude that phone app users don't get the same saved image structure.  I might try getting the app and then see what happens when I try the same.  Might be a while before I get round to this.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

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## #25 2021-06-10 23:10:43

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 4,685

### Re: Investigate Limit For Piecewise Function

Bob wrote:

I tried adding the 'i' in i.imgur to the link but got a server error.  I also tried...[lotsa things]

Hi Bob;

Yes, been there, done that...with the same degree of success.

The post #7 link just gets me to some kind of gallery page, with the main item being the image. The ID number is wrong too, as it's very different from the number I got from clicking the image.

It's not an 'image' url as such, one with an image-format extension (eg, jpg or png)...in the form accepted by the BBCode img tags.

With the BBCode image links that are posted here on MIF, just the image shows up...nothing else. No gallery, no peripherals, no ads.

Solution: I suggest selecting the already-uploaded-to-Imgur image with the cursor (or however you do it on a phone), and demanding the recalcitrant dumb smartphone to jolly well cough up the image address!!

"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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