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Roots and Coeffiencients (Polynomals) (1 Viewer)

Gintoki

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Well, we have our extension 1 maths test tomorrow...

The teacher has said that the hardest question is on roots and coeffients. We are allowed to bring in a sheet with anything we want on it...

I'm planning on taking in ones with the answers to some roots and coeffients, such as a^2 + b^2 + c^2 = (a + b + c)^2 -2(ab + ac + bc) (improvise those letters as alpha etc...)

If possible, I would to know these in the form similar to that above (working would be appreciated):

1) a^3 + b^3 + c^3
2) a^2 + b^2 +c^2 + d^2
3) a^3 + b^3 +c^3 + d^3

Any other common/known types would be appreciated.

Also, could some1 please list the different types of possibilites (not like above), such as where 1 root is twice the other. No need for working, just the different types youve seen...
 

shaon0

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Gintoki said:
Well, we have our extension 1 maths test tomorrow...

The teacher has said that the hardest question is on roots and coeffients. We are allowed to bring in a sheet with anything we want on it...

I'm planning on taking in ones with the answers to some roots and coeffients, such as a^2 + b^2 + c^2 = (a + b + c)^2 -2(ab + ac + bc) (improvise those letters as alpha etc...)

If possible, I would to know these in the form similar to that above (working would be appreciated):

1) a^3 + b^3 + c^3
2) a^2 + b^2 +c^2 + d^2
3) a^3 + b^3 +c^3 + d^3

Any other common/known types would be appreciated.

Also, could some1 please list the different types of possibilites (not like above), such as where 1 root is twice the other. No need for working, just the different types youve seen...
Is that even a test?
If you're smart enough and 3unit material. I think you should be able to improvise your answer.
After all maths is logic. So just think of it logically.
 

Timothy.Siu

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Gintoki said:
Well, we have our extension 1 maths test tomorrow...

The teacher has said that the hardest question is on roots and coeffients. We are allowed to bring in a sheet with anything we want on it...

I'm planning on taking in ones with the answers to some roots and coeffients, such as a^2 + b^2 + c^2 = (a + b + c)^2 -2(ab + ac + bc) (improvise those letters as alpha etc...)

If possible, I would to know these in the form similar to that above (working would be appreciated):

1) a^3 + b^3 + c^3
2) a^2 + b^2 +c^2 + d^2
3) a^3 + b^3 +c^3 + d^3

Any other common/known types would be appreciated.

Also, could some1 please list the different types of possibilites (not like above), such as where 1 root is twice the other. No need for working, just the different types youve seen...
1) a^3 + b^3 + c^3 =(a+b+c)^3-3(ab^2+2abc+ac^2+a^2b+a^2c+b^2c+bc^2)
................................=(a+b+c)^3-3((a+b+c)(ab+bc+ac)-abc)
 

tommykins

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1) if they ever ask for a^3 + b^3 + c^3, it's normally always a cubic. Sub a,b and c in and solve it simultaneously (rearrange to find a^3 + b^3 + c^3)

2) a^2 + b^2 +c^2 + d^2 = (a+b+c+d)^2 - 2(roots two at a time)

3) a^3 + b^3 +c^3 + d^3 - they should never ask you this.
 

Michaelmoo

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Gintoki said:
Well, we have our extension 1 maths test tomorrow...

The teacher has said that the hardest question is on roots and coeffients. We are allowed to bring in a sheet with anything we want on it...

I'm planning on taking in ones with the answers to some roots and coeffients, such as a^2 + b^2 + c^2 = (a + b + c)^2 -2(ab + ac + bc) (improvise those letters as alpha etc...)

If possible, I would to know these in the form similar to that above (working would be appreciated):

1) a^3 + b^3 + c^3
2) a^2 + b^2 +c^2 + d^2
3) a^3 + b^3 +c^3 + d^3

Any other common/known types would be appreciated.

Also, could some1 please list the different types of possibilites (not like above), such as where 1 root is twice the other. No need for working, just the different types youve seen...
The most common flaw of the HSC. The board of studies chooses to count asessments to contribute to 50% of the final HSC mark; yet we have schools like this giving people an unfair advantage...

Telling people "clues" or "hints" on a test, allowing them to bring in a sheet: FOR MATHS!!!! Pathetic if you ask me.
 

Timothy.Siu

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Michaelmoo said:
The most common flaw of the HSC. The board of studies chooses to count asessments to contribute to 50% of the final HSC mark; yet we have schools like this giving people an unfair advantage...

Telling people "clues" or "hints" on a test, allowing them to bring in a sheet: FOR MATHS!!!! Pathetic if you ask me.
thats not unfair, ur not doing the same internal tests, they can carry out they're tests in any fashion they want if its an internal test, they cud have a 30 minute test or 2 hours, cud omit some topics or watever, how is it unfair?doesn't affect you at all, it might just be unfair for some people doing the test,
it can actually be seen as a disadvantage because they cant do this in the HSC exam.
 

tommykins

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Michaelmoo said:
The most common flaw of the HSC. The board of studies chooses to count asessments to contribute to 50% of the final HSC mark; yet we have schools like this giving people an unfair advantage...

Telling people "clues" or "hints" on a test, allowing them to bring in a sheet: FOR MATHS!!!! Pathetic if you ask me.
errr how is it an advantage you bloody moron.
 

Continuum

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I dunno... bring allowed to bring in a sheet of whatever you want is abit suss.

And shaon0, you could have atleast helped him out instead of being all egotistical.
 

Michaelmoo

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tommykins said:
errr how is it an advantage you bloody moron.
Ever Heard of 50% of your final HSC mark comes from assessments?
 

Trebla

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Michaelmoo said:
Ever Heard of 50% of your final HSC mark comes from assessments?
Yes, but these marks are moderated/adjusted in accordance to the performance of the school's candidature in the external exams. So if the school performs poorly in the state-wide external exams, then those assessment marks are usually reduced.

To be honest, allowing a sheet of notes is not a good way to help prepare for the external exams because this doesn't allow students to develop familiarity with the strict examination environment of the external exams; not to mention it gives an inaccurate distribution of ranks because those who can recall the formulae are not discriminated between those who can't.
 
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M@ster P

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shaon0 said:
Is that even a test?
If you're smart enough and 3unit material. I think you should be able to improvise your answer.
After all maths is logic. So just think of it logically.
wtf the guy asked for help and you give him this??? who do you think you are " If you're smart enough and 3 unit material"?? dude seriously.....
 
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tommykins

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Michaelmoo said:
Ever Heard of 50% of your final HSC mark comes from assessments?
Ever heard of how raw marks mean nothing within your internal marks other than determining how to distribute your external marks?

It wouldn't matter if a school did an open book test, come HSC time - it all gets considered.
 

Iruka

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I can think of good reasons why a teacher might let people bring a formula sheet into an assessment. It encourages the students to learn how to summarize, which is certainly an important academic skill to develop.

And open book exams are not such a strange idea - you just make the questions alot harder, so it will distinguish the people who really understand the material well and can think for themselves, as opposed to just being good at rote learning formulae.
 

tommykins

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Yea iruka - we had an open book exam for our first research task.
 

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