The best way to start reasoning about limits is using graphs. Learn how we analyze a limit graphically and see cases where a limit doesn't exist.

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Zakoriya Ahmed

7 years agoPosted 7 years ago. Direct link to Zakoriya Ahmed's post “How do i know what is the...”

How do i know what is the limit if the graph has two functions ?

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(42 votes)

Lovetocode999

7 years agoPosted 7 years ago. Direct link to Lovetocode999's post “If the graph has two func...”

If the graph has two functions, then it depends on which of the two functions you are trying to find the limit of.

For example, say you have two graphs:

Function F(x) https://cdn.kastatic.org/ka-perseus-graphie/cfaecfcb3dd4f44b762a7f0a6dea53235be65418.svg

And function G(x) https://cdn.kastatic.org/ka-perseus-graphie/adfdea04d04764651f78e8585b0eb28c72056435.svg

When you are finding the limit it will specify whether it is function f or g in the limit function.(85 votes)

Vinesh Varathan

7 years agoPosted 7 years ago. Direct link to Vinesh Varathan's post “So, is it safe to say tha...”

So, is it safe to say that a limit exist for a function, if the graph of function at a x-value does not break (discontinued) even if it has another actual value at that same x-value point?

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(17 votes)

dantwisler

7 years agoPosted 7 years ago. Direct link to dantwisler's post “Yes. Limits are all abou...”

Yes. Limits are all about where it is heading, not the value at the location.

(39 votes)

d b

7 years agoPosted 7 years ago. Direct link to d b's post “When I used desmos to gra...”

When I used desmos to graph x/sin(x), x at 0 was defined. Isn't sin (0)=0, therefore making the function undefined at zero? I know I've done something obviously wrong...can you point it out to me? Thanks

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(17 votes)

Ms. Tran

7 years agoPosted 7 years ago. Direct link to Ms. Tran's post “Since you use desmos, you...”

Since you use desmos, you need to zoom in really close to the part of the graph where x=0 to see that x/sin(x) is not defined at x=0. You would not be able so see this if you graph it with a graphing calculator, however, if you press "2nd" and then "Table" you will see "error" at x=0, which means the function is not defined. I hope this helps.

(30 votes)

Alex

6 years agoPosted 6 years ago. Direct link to Alex's post “Does z-axis takes part in...”

Does z-axis takes part in Calculus?

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(14 votes)

cossine

6 years agoPosted 6 years ago. Direct link to cossine's post “Yep take a look at multiv...”

Yep take a look at multivariate calculus

(16 votes)

Vedic Patel

4 years agoPosted 4 years ago. Direct link to Vedic Patel's post “This is a bit of a broade...”

This is a bit of a broader question. How is limits applied in the real world? For example, derivatives and integrals are crucial to engineering and the sciences. Are limits just something used in pure mathematics or is there a more applicable use?

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(11 votes)

cossine

4 years agoPosted 4 years ago. Direct link to cossine's post “limits form the basis of ...”

limits form the basis of differentiation and integration.

If you want to find what happens at a particular time or will happen in the long run then limits are useful. Such as in time complexity.

(12 votes)

andrejoao.avelar500

7 years agoPosted 7 years ago. Direct link to andrejoao.avelar500's post “What about functions like...”

What about functions like f(x) = (1/x). Do those have limits?

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(6 votes)

Pat

7 years agoPosted 7 years ago. Direct link to Pat's post “Yes, it does except when ...”

Yes, it does except when the function f(x) approaches zero. It is undefined at this point; if you take the limit from the right as x+ >>> 0, it will grow without bound in the positive direction, and if you take the limit from the left as x- >>> 0, it will decrease without bound in the negative direction.

However, if you would take the limit of f(x) as x >>> infinity in either the negative or positive directions, the function would approach a value of 0.

So yes, the function 1/x would have a limit in every circ*mstance except at the point x = 0.(20 votes)

Alamin

a year agoPosted a year ago. Direct link to Alamin's post “Why can't we think about ...”

Why can't we think about a limit approaching more than 1 value? Of course I went on to the next sections and the concept of one sided limits makes this perhaps an uneducated question, but I must persist. It seems to me that what we get is a sort of complex vector if we forgo this "sided" limit idea and suppose that as we approach a limit (without saying from this side or that side) that even if we might be approaching more than one value, we don't have to fret as actually something unique and salient does indeed emerge (a 'complex' vector).

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(4 votes)

Venkata

a year agoPosted a year ago. Direct link to Venkata's post “The answer to that questi...”

The answer to that question isn't really that complicated. If we let a limit be two numbers, there's a really evident issue there. If I need to communicate this idea to someone, which number do I use? This causes ambiguity, because the question "What's the limit?" suddenly has two different answers instead of one. Hence, when we have two limits which aren't equal, for the sake of clarity, we say the limit doesn't exist.

Also, one sided limits aren't uneducated questions. You'll see how useful they can be later on

(16 votes)

jlin7753

a year agoPosted a year ago. Direct link to jlin7753's post “Problem 5 is confusing. W...”

Problem 5 is confusing. Where is function f(a) shown?

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(0 votes)

Venkata

a year agoPosted a year ago. Direct link to Venkata's post “They're just asking wheth...”

They're just asking whether the statement is true for any function f(x). Hence, no specific function was given.

(15 votes)

Noodi

5 years agoPosted 5 years ago. Direct link to Noodi's post “so, guys, I was wondering...”

so, guys, I was wondering whether this was easy enough or not, because I can do it in my sleep. BUY PEPSI NOT COLA

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(3 votes)

Frungi

5 years agoPosted 5 years ago. Direct link to Frungi's post “I'm not quite sure what y...”

I'm not quite sure what you're asking, but Pepsi is a brand of cola, so you can't do that. It's like trying to graph f(x) where x != x.

(6 votes)

ArvFar YDS

3 years agoPosted 3 years ago. Direct link to ArvFar YDS's post “In Desmos calculator, how...”

In Desmos calculator, how can I use the limit?

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(3 votes)

Iron Programming

3 years agoPosted 3 years ago. Direct link to Iron Programming's post “Howdy ArvFar, Unfortuna...”

Howdy ArvFar,

Unfortunately, Desmos does not have a limit tool. Desmos does have a

*table*feature that lets you solve the limit analytically (try searching the web for "Using Desmos to Solve Limits using Tables").Hope this helps.

(6 votes)