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Reply 1
xxclairexx04
im stuck i cant work out the rule for this nth term pattern ...please help me its for coursewrk :frown::frown:
6 24 54 96 150 << there the numbers


is it Un = 6n^2?
Reply 2
xxclairexx04
im stuck i cant work out the rule for this nth term pattern ...please help me its for coursewrk :frown::frown:
6 24 54 96 150 << there the numbers

\ / \ / \ / \ /
18 30 42 54 First difference
\ / \ / \ /
12 12 12 Second difference

So it's 0.5(12)n^2
= 6n^2

Ye-he-hes!!!
Reply 3
ZJuwelH
\ / \ / \ / \ /
18 30 42 54 First difference
\ / \ / \ /
12 12 12 Second difference

So it's 0.5(12)n^2
= 6n^2

Ye-he-hes!!!



what does the ^ stand for
Reply 4
xxclairexx04
what does the ^ stand for


'To the power of'. So 6n^2 reads as 6n squared.
Reply 5
So what's this courswork then? Is is squares in rectangles? if so look at the KEFW thread that has virtually the full solution and beyond.
Reply 6
Phil_C
So what's this courswork then? Is is squares in rectangles? if so look at the KEFW thread that has virtually the full solution and beyond.




Ireally dont understand wot nee1 is going on bout :frown:
Reply 7
...So do I get rep?
Reply 8
ZJuwelH
...So do I get rep?




whats rep ???? ..and could ne1 ezplain to me as easy as possible lol
Reply 9
xxclairexx04
whats rep ???? ..and could ne1 ezplain to me as easy as possible lol


Rep short for reputation, you can give someone positive or negative rep for a post by clicking the yellow box below the post (next to the edit button).

Do you mean you want the answer explained properly?
Reply 10
ZJuwelH
Rep short for reputation, you can give someone positive or negative rep for a post by clicking the yellow box below the post (next to the edit button).

Do you mean you want the answer explained properly?




Yes please if you dont mind
Reply 11
xxclairexx04
Yes please if you dont mind


Basically you find the differences between the terms. If they aren't the same you find the differences of these until they are the same. If you have found the dth difference to always be m then you raise n to the power of d and multiply by m/d, getting m/d(n)^d. Then bung in a value of n and look at the difference between it and the nth term you are looking at. Add or subtract a relevant number accordingly.

In this example we have a second difference of 12. So
m/d(n)^d=12/2(n)^2
=6n^2.
Now if we put in n=1 and compare to the first term, we get 6(1)^2=6. This is the same as the first term (where n=1) and throughout the series so we do not need to add or subtract any number, we have found the formula.

Hope it makes sense, sorry if it don't!
ZJuwelH
Basically you find the differences between the terms. If they aren't the same you find the differences of these until they are the same. If you have found the dth difference to always be m then you raise n to the power of d and multiply by m/d, getting m/d(n)^d. Then bung in a value of n and look at the difference between it and the nth term you are looking at. Add or subtract a relevant number accordingly.

In this example we have a second difference of 12. So
m/d(n)^d=12/2(n)^2
=6n^2.
Now if we put in n=1 and compare to the first term, we get 6(1)^2=6. This is the same as the first term (where n=1) and throughout the series so we do not need to add or subtract any number, we have found the formula.

Hope it makes sense, sorry if it don't!


How would you solve it if the number of terms given is not sufficient for a constant common difference to be found?
Reply 13
Ralfskini
How would you solve it if the number of terms given is not sufficient for a constant common difference to be found?


Don't think that sort of question would come up...
Haven't got a scooby if that does happen, been a while since I did P1 you see.
Reply 14
ZJuwelH
Basically you find the differences between the terms. If they aren't the same you find the differences of these until they are the same. If you have found the dth difference to always be m then you raise n to the power of d and multiply by m/d, getting m/d(n)^d. Then bung in a value of n and look at the difference between it and the nth term you are looking at. Add or subtract a relevant number accordingly.

In this example we have a second difference of 12. So
m/d(n)^d=12/2(n)^2
=6n^2.
Now if we put in n=1 and compare to the first term, we get 6(1)^2=6. This is the same as the first term (where n=1) and throughout the series so we do not need to add or subtract any number, we have found the formula.

Hope it makes sense, sorry if it don't!



so do u mean.....6x1=6.......wudnt i have 2 times by 2 ???coz u rit ^2
Reply 15
depends on where the sequence of numbers has come from. If it is from a build up of say poctorial patterns, like many GCSE maths coursworks do, then create the next few terms to investigate the differences between them and the differences of the differences etc. From there you can work out the type of power sequence you are dealing with.

Common first difference of "a" then Linear sequence of the form an where "n" is the position
Common 2nd difference of "a" then a quadratic sequence of (a/2)n^2
Common 3rd difference the cubic of form (a/6)n^3
etc

If the sequence is given as a set of numbers and you have found no common difference at the first few levels, 1st, 2nd 3rd etc, you can use a general formulae eg given 5 terms the sequnce could at most be n^4

Let the 5 terms by Z, Y, X, W, and V
then use an^4+bn^3+Cn^2+dn+e=... Z when n=1, Y when n=2 X when n=3 etc. 5 independent equations 5 unknowns so solvable.
Reply 16
xxclairexx04
so do u mean.....6x1=6.......wudnt i have 2 times by 2 ???coz u rit ^2


Do you mean if n=2? If so...
6n^2=6(2)^2
=6x4
=24

If that's not what you mean please clarify...
Reply 17
Phil_C
depends on where the sequence of numbers has come from. If it is from a build up of say poctorial patterns, like many GCSE maths coursworks do, then create the next few terms to investigate the differences between them and the differences of the differences etc. From there you can work out the type of power sequence you are dealing with.

Common first difference of "a" then Linear sequence of the form an where "n" is the position
Common 2nd difference of "a" then a quadratic sequence of (a/2)n^2
Common 3rd difference the cubic of form (a/6)n^3
etc

If the sequence is given as a set of numbers and you have found no common difference at the first few levels, 1st, 2nd 3rd etc, you can use a general formulae eg given 5 terms the sequnce could at most be n^4

Let the 5 terms by Z, Y, X, W, and V
then use an^4+bn^3+Cn^2+dn+e=... Z when n=1, Y when n=2 X when n=3 etc. 5 independent equations 5 unknowns so solvable.


...What he said.
Reply 18
ZJuwelH
Do you mean if n=2? If so...
6n^2=6(2)^2
=6x4
=24

If that's not what you mean please clarify...

than kyou sooooooooooooo much i fianly get it , ur better explaing then me teacher , thna alot sorry for taking up ur time
Reply 19
xxclairexx04
than kyou sooooooooooooo much i fianly get it , ur better explaing then me teacher , thna alot sorry for taking up ur time


Better than your teacher? Thanks heaps, I was hoping to become a teacher in my middle age...
'Twas my pleasure. Enjoy your work young Claire!