Text Assignment 1-1

course Mth 151

assignment #006006. `Query 6

College Algebra

05-14-2009

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23:58:45

Query 1.1.4 first 3 children male; conclusion next male. Inductive or deductive?

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RESPONSE -->

Inductive

confidence assessment: 3

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23:58:50

** The argument is inductive, because it attempts to argue from a pattern. **

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RESPONSE -->

self critique assessment: 3

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23:59:06

Query 1.1.8 all men mortal, Socrates a man, therefore Socrates mortal.

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RESPONSE -->

deductive

confidence assessment: 3

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23:59:15

** this argument is deductive--the conclusions follow inescapably from the premises.

'all men' is general; 'Socrates' is specific. This goes general to specific and is therefore deductive.

COMMON ERROR: because it is based on a fact, or concrete evidence.

Fact isn't the key; the key is logical inevitability. The argument could be 'all men are idiots, Socrates is an man, therefore Socrates is an idiot'. The argument is every bit as logical as before. The only test for correctness of an argument is that the conclusions follow from the premises. It's irrelevant to the logic whether the premises are in fact true. **

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RESPONSE -->

Got it

self critique assessment: 3

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23:59:41

Query 1.1.20 1 / 3, 3 / 5, 5/7, ... Probable next element.

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RESPONSE -->

11/13

confidence assessment: 3

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00:00:07

**The numbers 1, 3, 5, 7 are odd numbers. We note that the numerators consist of the odd numbers, each in its turn. The denominator for any given fraction is the next odd number after the numerator.

Since the last member listed is 5/7, with numerator 5, the next member will have numerator 7; its denominator will be the next odd number 9, and the fraction will be 7/9.

There are other ways of seeing the pattern. We could see that we use every odd number in its turn, and that the numerator of one member is the denominator of the preceding member.

Alternatively we might simply note that the numerator and denominator of the next member are always 2 greater than the numerator and denominator of the present member. **

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RESPONSE -->

The last number listed was 9/11....???

self critique assessment: 3

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00:01:51

Query 1.1.23 1, 8, 27, 64, ... Probable next element.

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RESPONSE -->

125 is the next but that is given in the book so 216

confidence assessment: 3

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00:02:04

** This is the sequence of cubes. 1^3 = 1, 2^3 = 8, 3^3 = 27, 4^3 = 64, 5^3 = 125.

The next element is 6^3 = 216.

Successive differences also work:

1 8 27 64 125 .. 216

7 19 37 61 .. 91

12 18 24 .. 30

6 6 .. 6 **

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RESPONSE -->

got it

self critique assessment: 3

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00:02:47

Query 1.1.36 11 * 11 = 121, 111 * 111 = 12321 1111 * 1111 = 1234321; next equation, verify.

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RESPONSE -->

11111 * 11111= 123454321

confidence assessment: 3

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00:02:52

** We easily verify that 11111*11111=123,454,321 **

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RESPONSE -->

got it

self critique assessment: 3

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00:03:29

Do you think this sequence would continue in this manner forever? Why or why not?

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RESPONSE -->

uhm... for the question before? no because after you have a 9 in the middle you don't have numbers to go up any more

confidence assessment: 3

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00:03:45

** You could think forward to the next few products: What happens after you get 12345678987654321? Is there any reason to expect that the sequence could continue in the same manner?

The middle three digits in this example are 8, 9 and 8. The logical next step would have 9, 10, 9, but now you would have 9109 in the middle and the symmetry of the number would be destroyed. There is every reason to expect that the pattern would also be destroyed. **

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RESPONSE -->

got it

self critique assessment: 3

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00:05:50

Query 1.1.46 1 + 2 + 3 + ... + 2000 by Gauss' method

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RESPONSE -->

2001?

confidence assessment: 2

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00:06:11

** Pair up the first and last, second and second to last, etc.. You'll thus pair up 1 and 2000, 2 and 1999, 3 and 1998, etc..

Each pair of numbers totals 2001.

Since there are 2000 numbers there are 1000 pairs. So the sum is 2001 * 1000 = 2,001,000 **

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RESPONSE -->

Ahh... 2001 * 1000... I knew I was missing something

self critique assessment: 3

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00:12:11

Query 1.1.57 142857 * 1, 2, 3, 4, 5, 6. What happens with 7? Give your solution to the problem as stated in the text.

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RESPONSE -->

I can't find a pattern in them for the first six numbers

confidence assessment: 1

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00:12:45

** Multiplying we get

142857*1=142857

142857*2= 285714

142857*3= 428571

142857*4=571428

142857*5= 714285

142857*6=857142.

Each of these results contains the same set of digits {1, 2, 4, 5, 7, 8} as the number 1428785. The digits just occur in different order in each product.

We might expect that this pattern continues if we multiply by 7, but 142875*7=999999, which breaks the pattern. **

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RESPONSE -->

Well I could have told you that. The text asks for a pattern

self critique assessment: 3

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00:12:55

What does this problem show you about the nature of inductive reasoning?

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RESPONSE -->

It can all change

confidence assessment: 3

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00:13:01

** Inductive reasoning would have led us to expect that the pattern continues for multiplication by 7.

Inductive reasoning is often correct it is not reliable. Apparent patterns can be broken. **

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RESPONSE -->

self critique assessment: 3

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&#This looks good. Let me know if you have any questions. &#

Text Assignment 1-1

course Mth 151

ìØ äzŰЇòƒJÖýâΤ„¤üû·ÚÑåassignment #006

006. `Query 6

College Algebra

05-14-2009

......!!!!!!!!...................................

23:58:45

Query 1.1.4 first 3 children male; conclusion next male. Inductive or deductive?

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RESPONSE -->

Inductive

confidence assessment: 3

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......!!!!!!!!...................................

23:58:50

** The argument is inductive, because it attempts to argue from a pattern. **

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RESPONSE -->

self critique assessment: 3

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23:59:06

Query 1.1.8 all men mortal, Socrates a man, therefore Socrates mortal.

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RESPONSE -->

deductive

confidence assessment: 3

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......!!!!!!!!...................................

23:59:15

** this argument is deductive--the conclusions follow inescapably from the premises.

'all men' is general; 'Socrates' is specific. This goes general to specific and is therefore deductive.

COMMON ERROR: because it is based on a fact, or concrete evidence.

Fact isn't the key; the key is logical inevitability. The argument could be 'all men are idiots, Socrates is an man, therefore Socrates is an idiot'. The argument is every bit as logical as before. The only test for correctness of an argument is that the conclusions follow from the premises. It's irrelevant to the logic whether the premises are in fact true. **

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RESPONSE -->

Got it

self critique assessment: 3

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23:59:41

Query 1.1.20 1 / 3, 3 / 5, 5/7, ... Probable next element.

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RESPONSE -->

11/13

confidence assessment: 3

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00:00:07

**The numbers 1, 3, 5, 7 are odd numbers. We note that the numerators consist of the odd numbers, each in its turn. The denominator for any given fraction is the next odd number after the numerator.

Since the last member listed is 5/7, with numerator 5, the next member will have numerator 7; its denominator will be the next odd number 9, and the fraction will be 7/9.

There are other ways of seeing the pattern. We could see that we use every odd number in its turn, and that the numerator of one member is the denominator of the preceding member.

Alternatively we might simply note that the numerator and denominator of the next member are always 2 greater than the numerator and denominator of the present member. **

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RESPONSE -->

The last number listed was 9/11....???

self critique assessment: 3

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00:01:51

Query 1.1.23 1, 8, 27, 64, ... Probable next element.

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RESPONSE -->

125 is the next but that is given in the book so 216

confidence assessment: 3

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00:02:04

** This is the sequence of cubes. 1^3 = 1, 2^3 = 8, 3^3 = 27, 4^3 = 64, 5^3 = 125.

The next element is 6^3 = 216.

Successive differences also work:

1 8 27 64 125 .. 216

7 19 37 61 .. 91

12 18 24 .. 30

6 6 .. 6 **

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RESPONSE -->

got it

self critique assessment: 3

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00:02:47

Query 1.1.36 11 * 11 = 121, 111 * 111 = 12321 1111 * 1111 = 1234321; next equation, verify.

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RESPONSE -->

11111 * 11111= 123454321

confidence assessment: 3

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00:02:52

** We easily verify that 11111*11111=123,454,321 **

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RESPONSE -->

got it

self critique assessment: 3

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00:03:29

Do you think this sequence would continue in this manner forever? Why or why not?

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RESPONSE -->

uhm... for the question before? no because after you have a 9 in the middle you don't have numbers to go up any more

confidence assessment: 3

.................................................

......!!!!!!!!...................................

00:03:45

** You could think forward to the next few products: What happens after you get 12345678987654321? Is there any reason to expect that the sequence could continue in the same manner?

The middle three digits in this example are 8, 9 and 8. The logical next step would have 9, 10, 9, but now you would have 9109 in the middle and the symmetry of the number would be destroyed. There is every reason to expect that the pattern would also be destroyed. **

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RESPONSE -->

got it

self critique assessment: 3

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00:05:50

Query 1.1.46 1 + 2 + 3 + ... + 2000 by Gauss' method

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RESPONSE -->

2001?

confidence assessment: 2

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......!!!!!!!!...................................

00:06:11

** Pair up the first and last, second and second to last, etc.. You'll thus pair up 1 and 2000, 2 and 1999, 3 and 1998, etc..

Each pair of numbers totals 2001.

Since there are 2000 numbers there are 1000 pairs. So the sum is 2001 * 1000 = 2,001,000 **

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RESPONSE -->

Ahh... 2001 * 1000... I knew I was missing something

self critique assessment: 3

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00:12:11

Query 1.1.57 142857 * 1, 2, 3, 4, 5, 6. What happens with 7? Give your solution to the problem as stated in the text.

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RESPONSE -->

I can't find a pattern in them for the first six numbers

confidence assessment: 1

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00:12:45

** Multiplying we get

142857*1=142857

142857*2= 285714

142857*3= 428571

142857*4=571428

142857*5= 714285

142857*6=857142.

Each of these results contains the same set of digits {1, 2, 4, 5, 7, 8} as the number 1428785. The digits just occur in different order in each product.

We might expect that this pattern continues if we multiply by 7, but 142875*7=999999, which breaks the pattern. **

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RESPONSE -->

Well I could have told you that. The text asks for a pattern

self critique assessment: 3

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00:12:55

What does this problem show you about the nature of inductive reasoning?

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RESPONSE -->

It can all change

confidence assessment: 3

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00:13:01

** Inductive reasoning would have led us to expect that the pattern continues for multiplication by 7.

Inductive reasoning is often correct it is not reliable. Apparent patterns can be broken. **

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RESPONSE -->

self critique assessment: 3

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&#Good responses. Let me know if you have questions. &#