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 03-06-2008, 06:34 PM #1 Daemon Poster     Join Date: Nov 2004 Posts: 1,246 A little math problem for you guys Express this sum in sigma notation: 1-(1/4)+(1/9)-(1/16)+(1/25) :-D __________________ __________________ Karma/rep is always appreciated 01010010011001010110010001100010011001010110000101 11001001100100 010011110111010101110100 There are only 10 kinds of people in this world. Those who can read binary, and those who can't.
 03-06-2008, 07:58 PM #2 Guru     Join Date: Jan 2008 Location: U.S. Posts: 7,841 Re: A little math problem for you guys K. I'm up to it. I'm not going to cheat. I don't know if there is a answer or not but I'll see. There should be. I'll post my answer edited in white. edit: Got it! 5 E (1/i^2) * (-1^(i+1)) i=1 __________________
 03-06-2008, 08:03 PM #3 Golden Master     Join Date: Mar 2006 Posts: 5,574 Re: A little math problem for you guys the sum of numbers from i=1 to i=5 of 1/-((-i)^2) I don't know how to make it look normal so I wrote it like you say it. __________________ AMD Athlon 64X2 4200+, 2 GB ram, 2 TB HDD, Ubuntu+SAMBA ♫ Lenovo T410, i5@ 2.4 GHz, 4 GB ram, 7
 03-06-2008, 08:06 PM #4 Guru     Join Date: Jan 2008 Location: U.S. Posts: 7,841 Re: A little math problem for you guys RubberChicken, I'm not sure if that works. That way you always get a negative number.
03-07-2008, 05:07 PM   #5
Golden Master

Join Date: Mar 2006
Posts: 5,574
Re: A little math problem for you guys

Quote:
 Originally Posted by JogaBonito1502 RubberChicken, I'm not sure if that works. That way you always get a negative number.
shoot, right... I was thinking 2 to the i, not i to the 2nd
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03-07-2008, 06:22 PM   #6
Daemon Poster

Join Date: Nov 2004
Posts: 1,246
Re: A little math problem for you guys

Quote:
 Originally Posted by Rubber314Chicken shoot, right... I was thinking 2 to the i, not i to the 2nd
Nice try.

Hint: To alternate positive and negative numbers put (-1)^x. When x is odd its negative, and when x is even its positive. Then if you wanted to reverse this you could put a negative in front of that. I hope I didn't just give the answer away completely ;-P
__________________
Karma/rep is always appreciated
01010010011001010110010001100010011001010110000101 11001001100100
010011110111010101110100

There are only 10 kinds of people in this world. Those who can read binary, and those who can't.

 03-08-2008, 12:58 AM #7 Fully Optimized     Join Date: Aug 2007 Posts: 2,186 Re: A little math problem for you guys The ultimate, true answer is as followed in white... 42 __________________ dude_56013: "Find something you love...and never work a day in your life" David Lindon: "Faggot"
 03-08-2008, 01:42 AM #8 Fully Optimized     Join Date: Dec 2007 Posts: 2,449 Re: A little math problem for you guys /\lol hahaha but seriously , im in grade 9 i dont have a clue what ur talking about __________________ (ASUS P5E X38)__(Q6600@3.4Ghz)__(Innod3D 8800GTS 512Mb 800/1920)__(4Gb corsair XMS2 800Mhz)__(Antec 900)__(Vista 64Bit)_(Zalman 9700) {3DMark06 15211}
 03-08-2008, 04:11 AM #9 Daemon Poster     Join Date: Nov 2007 Posts: 1,351 Re: A little math problem for you guys wt heck kinda math is this if you guys dont mind me asking =D __________________ __________________ Jesus died for me and you. AMD Athlon II 250 3.6ghz | ASRock N68C-S | Sapphire ATI Radeon HD 3850 PCI-E 512MB | SteelSeries Siberia USB Soundcard | Western Digital 250GB | LOGISYS 575watt PSU | Crucial 2GB ram DDR3