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# Portfolio Type 1 -- Parabola Investigation

179 posts in this topic

Can anyone help me with the parabola investigation? I am stuck in number 5 and 6. Thanks!

Sl=x1-x2

Sr=x3-x4

D= abs( Sl-Sr)

5.Determine whether a similar conjecture can be made for cubic polynomials

6. Consider whether the conjecture might be modified to include higher order polynomials.

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Doing the same one.. working on Q4 right now..

I'll post if i get to 5&6 tonight

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I'd want to help but there's not enough information...mind giving me some more info?

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I'd want to help but there's not enough information...mind giving me some more info?

The guy is asking about the last two questions... which builds up on 4-5 previous questions.. So unless you really want to spend 4 hours knowing what we're on about..

But to whoever is doing this.. QUESTION 6!?

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doing the same question as well T_T .

get stuck in number 5 too ><

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dont know about the cubical equation. there must be a conjecture too somewhere.

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.. anything about these points guys?

I've made a conjecture for cubic polynomials but I don't see how it can be generalized for all polynomials, since its not directly related to the first conjecture to begin with

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I had this task, finished it in March - there IS a conjecture for higher degree polynomials - when I did it, once I got the cubic conjecture, the higher level+ ones were all the same.

If you aren't getting that, go back and check your quadratic conjecture and make sure you have it working with any parabola/lines, then move on to the cubics.

Anyway, people in my class had a lot of difficulty getting the cubics...they weren't sure about how to get D. It took me a while, but you need to think about the relationships between the equations. Sorry, I don't know how much I'm allowed to help you since I've already done it.

jbhasin

Edited by jbhasin

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I'm pretty sure my quadratic conjecture is correct, I've done the proof and everything and it does work for all sorts of lines. The cubic one... the conjecture I did does work for all the lines I try, but it doesn't seem to have dependencies.. I'm not sure how much I could say as well, but the quadretic for example depended on several variables for the lines and the parabola itself, changing the values in a similar manner for cubic polynomials resulted in the same expected outcome for D.. which means I either came up with a super-conjecture here of I've missed something

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Well look at the relationships between the graphs:

parabolas and linear eqs intercepting

take a look at how you got D for the cubics

...

nth-degree polynomial and ...

Hopefully that doesn't make it too easy.

jbhasin

Edited by jbhasin

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Hi,

I have a serious problem with tasks 5 and 6.

I cannot figure out what I am supposed to find in 5. Anything that follows any patterns is that when I subtract all x's in a similar way as it was in previous exercises D is always 0. But it seems still quite illogical. Can anyone confirm if it is correct? Or maybe somebody would be eager to help me?

Edited by sweetnsimple786

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When I read what jbhasin told me.. I just thought I couldn't make use of it, and I didn't.. but he seemed afraid that "it would make it too easy" and I kept thinking "no it doesn't".. but I literally thought of the solution WHILE I WAS ASLEEP (we IB victims go through stuff like that.. y'all know that) and so I understand now that saying anything more than what has been mentioned is... just... too.. direct.

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Ok, thanks a lot. I'll keep trying, but today my brain is devastated by maths and tok.

According to what you say it should be quite easy and even obvious, am I right?

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Hi. I am also doing this portfolio on parabolas.

I am stuck at 5.

I have come up with many unique observations like D=0 and that the sum of the roots on the y=x line and y=2x lines will give the sum of the roots (r1+r2+r3).

But what's the point of all these? Must the conjecture be the same as the one from Q1 to Q4.

Thanks

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Does anybody know if the two intersecting lines MUST be straight lines?

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hmm seems like everyone got the same prob... hmm my deadline is in 2 days time

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Does anybody know if the two intersecting lines MUST be straight lines

definitely it must be straight lines , otherwise what? you want to change it into curve???

haha I just finish question 2 ) 10 pages so far , not too bad ) another 10 for question 3 and another 10 for question 4 will sound good =)) omg

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definitely it must be straight lines , otherwise what? you want to change it into curve???

haha I just finish question 2 ) 10 pages so far , not too bad ) another 10 for question 3 and another 10 for question 4 will sound good =)) omg

hmm this is type 1 you know. you don't want to make it too long, your examiner will either commit suicide for having to read 40 pages or then mark you down for being too wordy in the communication section.

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Hmm.. whats the average length of a type 1 IA? Mine in total turned out to be ~24 pages but with spacing for graphs, etc. but I covered all points and tried not to be repetitive. so I don't know about that..

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I red in other thread that D is always equal to zero (D=0) for Q5 and Q6. I investigated it, but this answer only works for Q5. When I try with polynomials higher I get numbers like 0.00153..., very closely to zero, but no zero. Can somebody help us? Thank you in advance =)

P.D. Sorry for my English, I am not a native speaker of English ^^

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Can anyone help me with the parabola investigation? I am stuck in number 5 and 6. Thanks!

Sl=x1-x2

Sr=x3-x4

D= abs( Sl-Sr)

5.Determine whether a similar conjecture can be made for cubic polynomials

6. Consider whether the conjecture might be modified to include higher order polynomials.

it's abs(-1/a) not abs(1/a) pplz

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Hint: That isn't the whole conjecture

jbhasin

1 person likes this

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If you experiment with more lines and your parabola, you find that the conjecture is actually more general than D= (-1/x)

...

I REALLLY NEEED HELP WITH 5 ...and 6 I guess although i haven't even begun to consider it yet

my portfolio is due on monday (2 days)

I realize that D=0, and that can be found by doing (x6-x4-x2)-(x5-x3-x1)

but i don't know if that's the only way, or even the right way

and i can't really figure out what the conjecture would be

is it just always zero as long as SL and SR are present...i figured out that SM doesn't work out on its own, but as long as you have the intercepts for SL and SR you get zero

i just need help, or for someone to tell me if i'm at all on the right track

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Same here - So D=0, but so what? What do you do from there?

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I am also stuck in q5 and q6 and need help asap