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#1 2016-04-19 20:46:25
- Sierra
- Guest
Lesson 20 Sequences and Series
Hi, I'm stuck on this math problem and I really need help. Please tell give me a easy way to do these problems because my math is not the greatest >< Some of the links are the problems and I'm new here so I apologize ><
For questions 1 and 2, find the first 6 terms and the 100th term of the explicitly-defined sequence.
1. 
2. 
For problems 9 and 10, write each sum using summation notation.
9.2 + 5 + 8 + 11 + ... + 29
10. 6 - 12 + 24 - 48 + ...
11. Find the sum of the arithmetic sequence 2, 4, 6, 8, ..., 70.
12. Find the sum of the geometric sequence
http://www.sc.whitmoreschool.org/sec/students/classes/scalgebra_2/lesson35_files/clip_image107.gif
For problems 13 and 14, find the sum of the first n terms of the sequence. The sequences are either arithmetic or geometric.
13. -1, 11, -121, ...; n = 9
14. 14, 8, 2,...; n=9
15. Determine whether the infinite series is equal to a real number. If so, find the sum.
http://www.sc.whitmoreschool.org/sec/students/classes/scalgebra_2/lesson35_files/clip_image121.gif
#2 2016-04-20 03:40:32
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Lesson 20 Sequences and Series
Hi;
my math is not the greatest
Out of all the billions of people who ever tried to do math only Isaac Newton ever found it easy.
I fixed up your post a bit so everyone can see the problem easily.
Let's try 2)
These are easy, you just start with the counting numbers 1,2,3,4,... and substitute them for n.
Can you do
for me?In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#3 2016-04-20 07:59:38
- 90sginger
- Member
- Registered: 2016-04-20
- Posts: 19
Re: Lesson 20 Sequences and Series
Hi;
my math is not the greatest
Out of all the billions of people who ever tried to do math only Isaac Newton ever found it easy.
I fixed up your post a bit so everyone can see the problem easily.
Let's try 2)
These are easy, you just start with the counting numbers 1,2,3,4,... and substitute them for n.
Can you do
for me?
d4 = (4)^2 - 5(4)
d4 = 16 - 20
d4 = -4
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#4 2016-04-20 08:12:42
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Lesson 20 Sequences and Series
That is correct!
Can you do 1) now or need help.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#5 2016-04-20 08:29:29
- 90sginger
- Member
- Registered: 2016-04-20
- Posts: 19
Re: Lesson 20 Sequences and Series
That is correct!
Can you do 1) now or need help.
I need help, if you can!
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#6 2016-04-20 08:35:28
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Lesson 20 Sequences and Series
Start with 1 and plug it into the formula wherever there is an n.
We start with n = 1
What is
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
Offline
#7 2016-04-20 08:55:52
- 90sginger
- Member
- Registered: 2016-04-20
- Posts: 19
Re: Lesson 20 Sequences and Series
Start with 1 and plug it into the formula wherever there is an n.
We start with n = 1
What is
V2 = 4/2+2 = 4/4
Should I do the same with V3?
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#8 2016-04-20 08:58:21
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Lesson 20 Sequences and Series
That is correct and do it for 3).
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
Offline
#9 2016-04-20 09:20:25
- 90sginger
- Member
- Registered: 2016-04-20
- Posts: 19
Re: Lesson 20 Sequences and Series
That is correct and do it for 3).
v3 = 4/3 + 3 = 4/6
v4 = 4/4 + 4 = 4/8
I added v4 just in case.
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#10 2016-04-20 09:31:16
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Lesson 20 Sequences and Series
Both v3 and v4 are incorrect, please try again.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
Offline
#11 2016-04-20 09:51:05
- 90sginger
- Member
- Registered: 2016-04-20
- Posts: 19
Re: Lesson 20 Sequences and Series
Both v3 and v4 are incorrect, please try again.
v3 = 4/3 + 2 = 4/5
v4 = 4/4 + 2 = 4/6
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#12 2016-04-20 10:02:29
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Lesson 20 Sequences and Series
That is correct.
Can you get
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
Offline
#13 2016-04-20 10:21:16
- 90sginger
- Member
- Registered: 2016-04-20
- Posts: 19
Re: Lesson 20 Sequences and Series
That is correct.
Can you get
v100 = 4/100 + 2 = 4/102
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#14 2016-04-20 10:29:18
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Lesson 20 Sequences and Series
Can you reduce that?
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
Offline
#15 2016-04-20 11:44:24
- 90sginger
- Member
- Registered: 2016-04-20
- Posts: 19
Re: Lesson 20 Sequences and Series
Can you reduce that?
v100 = 4/100 + 2 = 4/102 = 2/51
Last edited by 90sginger (2016-04-20 11:48:56)
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#16 2016-04-20 11:55:44
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Lesson 20 Sequences and Series
That is correct.
What is
for 2)?In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
Offline
#17 2016-04-20 13:54:00
- 90sginger
- Member
- Registered: 2016-04-20
- Posts: 19
Re: Lesson 20 Sequences and Series
That is correct.
What is
for 2)?
d100 = (100)^2 - 5(100)
d100 = 1000 - 500
d100 = 500
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#18 2016-04-20 14:34:26
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Lesson 20 Sequences and Series
Hmmm. Are you sure 100 * 100 =1000?
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
Offline
#19 2016-04-20 15:15:22
- 90sginger
- Member
- Registered: 2016-04-20
- Posts: 19
Re: Lesson 20 Sequences and Series
Hmmm. Are you sure 100 * 100 =1000?
100 * 100 = 10,000
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#20 2016-04-20 15:32:11
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Lesson 20 Sequences and Series
Yep!
Now what is d100?
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
Offline
#21 2016-04-20 15:40:04
- 90sginger
- Member
- Registered: 2016-04-20
- Posts: 19
Re: Lesson 20 Sequences and Series
Yep!
Now what is d100?
d100 = (100)^2 - 5(100)
d100 = 10000 - 500
d100 = 9,500
Should I put this after the d4?
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#22 2016-04-20 16:14:00
- Monox D. I-Fly
- Member
- From: Indonesia
- Registered: 2015-12-02
- Posts: 2,000
Re: Lesson 20 Sequences and Series
d100 = 9,500
Should I put this after the d4?
Nope, he was just testing you. If you can do d1, d2, d3, d4, and d100, surely you can do d5 and d6 by yourself.
Actually I never watch Star Wars and not interested in it anyway, but I choose a Yoda card as my avatar in honor of our great friend bobbym who has passed away.
May his adventurous soul rest in peace at heaven.
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#23 2016-04-20 16:42:29
- 90sginger
- Member
- Registered: 2016-04-20
- Posts: 19
Re: Lesson 20 Sequences and Series
90sginger wrote:d100 = 9,500
Should I put this after the d4?
Nope, he was just testing you. If you can do d1, d2, d3, d4, and d100, surely you can do d5 and d6 by yourself.
Ah okay, I did that and I got:
d5 = (5)^2 - 5(5)
d5 = 25 - 25 = 0
d6 = (6)^2 - 5(6)
d6 = 36 - 30 = 6
Do I stop there or keep going?
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#24 2016-04-20 16:44:09
- Monox D. I-Fly
- Member
- From: Indonesia
- Registered: 2015-12-02
- Posts: 2,000
Re: Lesson 20 Sequences and Series
For questions 1 and 2, find the first 6 terms and the 100th term of the explicitly-defined sequence.
So...?
Actually I never watch Star Wars and not interested in it anyway, but I choose a Yoda card as my avatar in honor of our great friend bobbym who has passed away.
May his adventurous soul rest in peace at heaven.
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#25 2016-04-20 16:49:59
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Lesson 20 Sequences and Series
Hi;
Do I stop there or keep going?
You just need v5 and v6 and you are done with the first two questions.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
Offline