11 replies to this topic

[mewminator]

Sequence P: 7, 5, 3, 1, p
Sequence Q: 1, 8, 27, 64, q
Sequence R: 1/2, 2/3, 3/4, 4/5, r
Sequence S: 4, 9, 16, 25, s
Sequence T: 1, 3, 9, 27, t,
Sequence U: 3, 6, 7, −2, u
Where p,q,r,s,t and u are the 8th terms of each sequence
Find each.

[Pickett]

Spoiler for general answers

P(n) = 9 - 2(n)
Q(n) = n³
R(n) = n / (n+1)
S(n) = (n+1)²
T(n) = 3^(n-1)
U = Still working

But you can plug in whatever "n" you want to those...

[mewminator]

Spoiler for general answers

P(n) = 9 - 2(n)
Q(n) = n³
R(n) = n / (n+1)
S(n) = (n+1)²
T(n) = 3^(n-1)
U = Still working

But you can plug in whatever "n" you want to those...

u is what gets everyone

[David W]

This is what I have so far (similar/ the same as Pickett's solutions)

Spoiler for What I Got...

P: 7, 5, 3, 1
7-2(n-1)
Q: 1, 8, 27, 64
n3
R: 1/2, 2/3, 3/4, 4/5
n/(n+1)
S: 4, 9, 16, 25
(n+1)2
T: 1, 3, 9, 27
3(n-1)
U: 3, 6, 7, -2
8th Terms (n=8)
p = -7
q = 512
r = 8/9
s = 81
t = 2187
u = ?

Edited by David W, 25 October 2011 - 09:04 PM.

[curr3nt]

Spoiler for u=

-298 seriously?

-edit-
http://jeff.aaron.ca...xtnumber?size=4
-(4/3)n^3 + 7n^2 - (26/3)n + 6

Edited by curr3nt, 25 October 2011 - 09:13 PM.

[shakingdavid]

Spoiler for u

U = S - T, easy as pie so u = -2106

[mewminator]

@curr3nt try again
@shakingdavid that's correct

[curr3nt]

@curr3nt try again
@shakingdavid that's correct

Just because it isn't what you wanted doesn't mean it doesn't work.

[mewminator]

Just because it isn't what you wanted doesn't mean it doesn't work.

I wrote it down on my calculator so unless you wrote the equation wrong your answer is wrong. I tried it on the first 3 terms.

[shakingdavid]

I wrote it down on my calculator so unless you wrote the equation wrong your answer is wrong. I tried it on the first 3 terms.

Actually his equation is correct, but your calculator may be wrong. Be sure to make the calculations in the correct order: parentheses first, then powers, then multiplication and division, and finally addition/subtraction.

For n=1, we have n^3=n^2=n=1, so -(4/3)*1 + 7*1 - (26/3)*1 + 6 = -4/3 + 7 - 26/3 + 6 = -30/3 + 13 = -10 + 13 = 3
For n=2, we have n^3=8, n^2=4, so -(4/3)*8 + 7*4 - (26/3)*2 + 6 = -32/3 + 28 -52/3 + 6 = -84/3 + 34 = -28 + 34 = 6
For n=3, we have n^3=27, n^2=9, so -(4/3)*27 + 7*9 - (26/3)*3 + 6 = -108/3 + 63 - 78/3 + 6 = -186/3 + 69 = -62 + 69 = 7