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The Fibonacci Sequence

The Fibonacci Sequence

Posers and Puzzles

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Originally posted by THUDandBLUNDER
If you differentiate e^x wiith respect to x it remains unaffected.
That is, letting y = e^x, dy/dx = e^x
But d(e^x)/dy = dy/dy = 1
e^x has been changed into a constant.
Differentiation, integration and exponentials etc are what put me off mathematics forever. Until then I had a reasonably good concept and feel for the subject. But at this point I stopped being able to build a mental picture of what it was about. I must be a thick c888 or something.
Anyways, I shall tell it to my brother. He has a PhD in Mathematics. That will be the true acid test as to whether it is funny or not. 😛

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Originally posted by jimslyp69
Differentiation, integration and exponentials etc are what put me off mathematics forever. Until then I had a reasonably good concept and feel for the subject. But at this point I stopped being able to build a mental picture of what it was about. I must be a thick c888 or something.
Anyways, I shall tell it to my brother. He has a PhD in Mathematics. That will be the true acid test as to whether it is funny or not. 😛
Don't worry. One only really needs algebra anyway. And that can be largely intuitive, if that's the right word.

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Originally posted by Bowmann
Don't worry. One only really needs algebra anyway. And that can be largely intuitive, if that's the right word.
Cheers for the words of encouragement but I suppose that all depends on what you want to do with it. Just lucky I don't want to be a programmer really. 😲

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Originally posted by jimslyp69
Cheers for the words of encouragement but I suppose that all depends on what you want to do with it. Just lucky I don't want to be a programmer really. 😲
I managed to write programs using O-level maths.

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Originally posted by Bowmann
I managed to write programs using O-level maths.
I got an A in GCSE maths but I wouldn't say i was anywhere near O level standard. My Brother had an O level maths exercise book from 1969, that he acqured from my Grand Ma. He had serious difficulties solving the problems in it whilst he was at A level standard in 1990.

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Originally posted by THUDandBLUNDER
But his original post didn't even contain a question mark.
So he must be kindly telling us that a person called Ever heard of the Fibonacci sequence, right? 😵

Therefore, in order to give this thread a raison d'etre, here is a joke:

e^x is walking down the road one day when he meets several other functions coming the other way. One of them ...[text shortened]... Hi, I'm e^x"

"Hello," replied the differential, grinning broadly, "I'm d/dy"


d/dy could not split e^x.
e^x is a real tough guy.
To d/dy's dismay, all it can do is put e^x under the table---to try to humiliate e^x.
e^x just keeps laughing down there.

y = e^x

d/dx y = d/dx e^x
dy/dx = e^x ------nothing doing.

d/dy y = d/dy e^x
dy/dy = e^x dx/dy
1 = e^x dx/dy
dx/dy = 1 / e^x -----underneath, but still intact.

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Originally posted by phgao
d/dy could not split e^x.
e^x is a real tough guy.
To d/dy's dismay, all it can do is put e^x under the table---to try to humiliate e^x.
e^x just keeps laughing down there.

y = e^x

d/dx y = d/dx e^x
dy/dx = e^x ------nothing doing.

d/dy y = d/dy e^x
dy/dy = e^x dx/dy
1 = e^x dx/dy
dx/dy = 1 / e^x -----underneath, but still intact.
Amusing, but it lacks a punchline.

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Originally posted by phgao
d/dy could not split e^x.
e^x is a real tough guy.
To d/dy's dismay, all it can do is put e^x under the table---to try to humiliate e^x.
e^x just keeps laughing down there.

y = e^x

d/dx y = d/dx e^x
dy/dx = e^x ------nothing doing.

d/dy y = d/dy e^x
dy/dy = e^x dx/dy
1 = e^x dx/dy
dx/dy = 1 / e^x -----underneath, but still intact.
y = e^x
dy/dx = e^x
dx/dy = e^-x
Fair enough.

But we re not differentiating x wrt y
We are differentiating e^x wrt y
Having done so, we get a constant (1)

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Originally posted by THUDandBLUNDER
What's the square root of 69?

Eight something...
BTW the full equation for that is:

B4IFQRU/18 = 69^0.5

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Originally posted by sonhouse
BTW the full equation for that is:

B4IFQRU/18 = 69^0.5
18? You are almost normal.
I remember B4Iroot(U)RU/16

I guess we Brits are just more liberal than you homebred Yankees.

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I heard a really funny (to a maths geek) story about little Polly Nomial once, and how she lost her convergency. It's probably rolling around the internet somewhere if I can be bothered...

...ah yes, here's a version. It was funnier when read aloud with lots of meaningful pauses.

http://www-users.cs.york.ac.uk/~susan/joke/polly.htm

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Originally posted by orfeo
I heard a really funny (to a maths geek) story about little Polly Nomial once, and how she lost her convergency. It's probably rolling around the internet somewhere if I can be bothered...

...ah yes, here's a version. It was funnier when read aloud with lots of meaningful pauses.

http://www-users.cs.york.ac.uk/~susan/joke/polly.htm
That's a fcuked up story. It's about a function being raped and getting pregnant, no? And the cautionary at the end is to keep your kids locked up forever. It was probably funnier in the 50's, although I will say the language was cleverly used.