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#1851 2012-09-11 02:10:43

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,603

Re: What do you think?

I can't take your place because I do not have a dog...


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#1852 2012-09-11 02:13:44

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 88,727

Re: What do you think?

Post # 1797 is a good one.


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#1853 2012-09-11 02:21:33

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,603

Re: What do you think?

I have seen it, but I am not very good at asymptotics.


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#1854 2012-09-11 02:23:08

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 88,727

Re: What do you think?

I do not mind. Do the best you can or try the one in "Is this cool with you."


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#1855 2012-09-30 00:09:26

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 88,727

Re: What do you think?

New problem:

D is given these 5 points ( -2 , 2 ),( -1 , 1 )( 0 , 0 ), ( 1 , 1 ), ( 2 , 2 ) and asked to fit a quadratic through them. Sounds easy enough but it has the additional constraint that no point can differ from the predicted point by more than .25

He remembers something about least squares and tries a quadratic regression. He plugs the points into his favorite spreadsheet and comes up with

He checks all his points by plugging in x and seeing how far off he is. Plugging in x = -2 he gets y = 2.0571428 which only differs by .0571428, x =1 is also less than .25. When he plugs in 0 he gets .34285714 when he should get 0. The error is .34285714 and that is greater than .25. He is stuck and turns to our panel.

A says) Just keep using higher and higher regressions. Try cubic regression.

D says) It has to be a quadratic.

A says) Kaboobly doo! Do not bother me with details like that.

B says) You can use a certain type of fit called...

C says) A is probably right, try a cubic and then a quartic and then a quintic ad infinitum.

D says) It has to be a quadratic.

E says) Go with B he is right, there is a way.

Can you do it? Can you find the quadratic?


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#1856 2012-10-29 14:01:56

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 88,727

Re: What do you think?

New problem:

Two large towers are erected on a perfectly level piece of ground. We will call them tower A and tower B. Two marks are drawn on the towers near the top. When a line is drawn from the base of tower A to the mark on tower B it is 50 meters long. When a line is drawn from tower B to tower A's mark it is 40 meters long. The two lines intersect between the towers 10 meters above the ground. How far are the towers away from each other?

Can you get the exact answer for full credit. Can you get any answer for partial credit? The closer the better.


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#1857 2012-10-31 11:41:39

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,603

Re: What do you think?

Hi bobbym

My first answer is


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#1858 2012-10-31 11:59:54

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 88,727

Re: What do you think?

Hi;


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#1859 2012-10-31 12:02:02

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,603

Re: What do you think?

You mean in the number of digits or exactness?


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#1860 2012-10-31 12:03:51

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 88,727

Re: What do you think?

Hi;


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#1861 2012-10-31 12:09:34

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,603

Re: What do you think?

Hi


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#1862 2012-10-31 12:14:18

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 88,727

Re: What do you think?

Hi;


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#1863 2012-10-31 12:25:43

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,603

Re: What do you think?


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#1864 2012-10-31 12:26:56

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 88,727

Re: What do you think?

Hi;


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#1865 2012-10-31 12:29:22

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,603

Re: What do you think?

Hi


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#1866 2012-10-31 12:35:54

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 88,727

Re: What do you think?

Hi;


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

#1867 2012-10-31 12:37:52

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,603

Re: What do you think?

Hahahahahahahahaha...

Are you sure?


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#1868 2012-10-31 12:39:44

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 88,727

Re: What do you think?

Hi;


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

#1869 2012-10-31 21:36:18

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,603

Re: What do you think?

Hi

Suddenly I am getting

answer.


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#1870 2012-10-31 22:36:37

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 88,727

Re: What do you think?

Hi;


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

#1871 2012-10-31 22:54:10

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,603

Re: What do you think?

I know. But, are you sure it is incorrect?


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#1872 2012-10-31 22:56:46

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 88,727

Re: What do you think?


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

#1873 2012-10-31 23:01:50

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,603

Re: What do you think?

Hi

I figured out what was wrong. I was using 60 and 50 instead of 50 and 40...


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#1874 2012-10-31 23:05:51

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 88,727

Re: What do you think?

Hi anonimnystefy;


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#1875 2012-10-31 23:17:06

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,603

Re: What do you think?

Hi bobbym

Last edited by anonimnystefy (2012-10-31 23:21:13)


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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