why not

This is a discussion on *Riddles/Math/Logic* within the **A Brief History of Cprogramming.com** forums, part of the Community Boards category; why not...

- 08-31-2002 #16

- 08-31-2002 #17

- 08-31-2002 #18

- 08-31-2002 #19
See, I'm not completly stupid.

Riddle: (easy one)

The Pope has it but he does not use it. Your father has it but your mother uses it. Nuns do not need it. Your lady friend's husband has it and she uses it. What is it?

- 08-31-2002 #20
*Originally posted by Driveway*

**See, I'm not completly stupid.**

Riddle: (easy one)

The Pope has it but he does not use it. Your father has it but your mother uses it. Nuns do not need it. Your lady friend's husband has it and she uses it. What is it?hello, internet!

- 08-31-2002 #21

- 09-01-2002 #22
My riddle: (I gave up on the other one)

A hunter sets out from camp at 4 o'clock in the morning with a compass. According to the compass, he travels due south for 4 hours. At that time he sees a bear and kills it (he is a hunter after all). He drags the bear with him for 4 hours due east, and he takes a quick break. Then he drags the bear due north for 4 hours at which time he arrives back at his camp where he decides he doesn't want the bear after all, packs his SUV and leaves.

So what color was the bear that he killed?

- 09-01-2002 #23

- 09-01-2002 #24

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What has been done by every male, except for one? Normally does it with many, but can do it by herself. Is world-renowned for her infinite skill and great noise. And gives many great pleasure.

P.S. You'll probably never get this.

- 09-02-2002 #25
## A maths one...

Well here's a maths one (quite easy):

By considering the series,

*1 + t + t^2 + t^3 + ... + t^n*

sum the series,

*1 + 2t + 3t^2 + 4t^3 + ... + nt^(n-1)*

for*t*not = 1, where a^b denotes*a*raised to the*b*th power.

Have fun!Richard Hayden. (rahaydenuk@yahoo.co.uk)

Webmaster: http://www.dx-dev.com

DXOS (My Operating System): http://www.dx-dev.com/dxos

PGP: 0x779D0625

- 09-02-2002 #26

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Good problem!

I think it's

(n * t^(n+1) - (n + 1) * t^n + 1) / (t-1)^2

I even sort of proved it.

- 09-03-2002 #27
*Originally posted by Nick*

**Good problem!**

I think it's

(n * t^(n+1) - (n + 1) * t^n + 1) / (t-1)^2

I even sort of proved it.Richard Hayden. (rahaydenuk@yahoo.co.uk)

Webmaster: http://www.dx-dev.com

DXOS (My Operating System): http://www.dx-dev.com/dxos

PGP: 0x779D0625

- 09-03-2002 #28

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This is how I found the answer

Code:1 + t + t^2 + t^3 + ... + t^n + t + t^2 + t^3 + .... + t^n + t^2 + t^3 + ... + t^n + t^3 + ... + t^n .... + t^n

1 + 2t + 3t^2 + 4t^3 + ... + nt^(n-1)

After that I solved the sums and then used induction

to prove/check the final answer.

- 09-03-2002 #29
*Originally posted by Nick*

**This is how I found the answer**

Code:1 + t + t^2 + t^3 + ... + t^n + t + t^2 + t^3 + .... + t^n + t^2 + t^3 + ... + t^n + t^3 + ... + t^n .... + t^n

1 + 2t + 3t^2 + 4t^3 + ... + nt^(n-1)

After that I solved the sums and then used induction

to prove/check the final answer.*1 + t + t^2 + t^3 + ... + t^n*. Can you/anyone else find it?

You'll kick yourselves...

Good Luck!Richard Hayden. (rahaydenuk@yahoo.co.uk)

Webmaster: http://www.dx-dev.com

DXOS (My Operating System): http://www.dx-dev.com/dxos

PGP: 0x779D0625

- 09-03-2002 #30

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I noticed that derivative

of 1 + t + t^2 + t^3 + ... + t^n

is the 0 + 1 + 2t + 3t^2 +... + nt^(n-1)

I'm sure you could give a prove or solve it some how

using this?

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