document.write( "Question 41021: An infinite geometric series has 1 and 1/5 as its first two terms: 1,1/5,1/25,1/125,..... What is the sum, S, of the infinite series?
\n" ); document.write( "a)1/25
\n" ); document.write( "b)1/4
\n" ); document.write( "c)1
\n" ); document.write( "d)5/4
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Algebra.Com's Answer #26488 by mszlmb(115)\"\" \"About 
You can put this solution on YOUR website!
I LOVE infinite series.
\n" ); document.write( "ok so 1+1/5+1/25+1/125+1/625...
\n" ); document.write( "1+.2+.04+.008+.0016
\n" ); document.write( "or 1+(1*2)/10+(1*4)/100+(1*8)/1000...
\n" ); document.write( "or 1+...
\n" ); document.write( "we have 1/5+1/25=6/25+1/125=31/125+1/625=156/625 and so on
\n" ); document.write( "so y=\"%28%28%28%28%281%2A5%2B1%29%2A5%2B1%29%2A5%2B1%29%2A5%2B1%29%2A5%2B1%29\"
\n" ); document.write( "or, ignoring the order of whatever its called,
\n" ); document.write( "we add one and multiply by 5 over and over again, infinitely, over
\n" ); document.write( "0+1*5+1*5+1*5...
\n" ); document.write( "_____________
\n" ); document.write( "5(5)(5)(5)(5)
\n" ); document.write( "yielding \"%28%28%28%28%280%2B1%295%2B1%295%2B1%295%2B1%295%2B1%295...%29%2F5%2A5%2A5%2A5%2A5...\"
\n" ); document.write( "or \"%28%280%2B1%29%2F5%29%2A%28125%2F6%29\"\r
\n" ); document.write( "\n" ); document.write( "ok forget all of that, a lot of it is wrong. But be ready to refer to it. don't worry if it made no sense.\r
\n" ); document.write( "\n" ); document.write( "now im very sorry, i feel quite childish in terms of intellect; perhaps you can solve it from here..
\n" ); document.write( "I got \"E%28x%2F5%5Ex%29\" ...:P I can't solve it anymore!\r
\n" ); document.write( "\n" ); document.write( "I do, however, feel like much less of a mathematical amateur telling you that the answer is obviously, of the four choices listed above, 5/4, because its the only number higher than one, and seeing as how this infinite series is 1+ something.. well, you can make the connection:)\r
\n" ); document.write( "\n" ); document.write( "I would REALLY appreciate it if you could perhaps teach me by way of email how to get the solution when you do\r
\n" ); document.write( "\n" ); document.write( "yours truly, <-)))><(((->
\n" ); document.write( "
\n" ); document.write( "sorry about all that, i worked on it today..here's what iv come up with..
\n" ); document.write( "
so we have 1+.2+.04+.008 etc.
Do you see the pattern, again, of *2 and *5?

\n" ); document.write( "
This can be expressed as \"2%5Ex%2F10%5Ex\". That's to get any the xth number (ie the 5th number is 32/100000, or .000032; try it.)

\n" ); document.write( "
Of course, this is not what we want, we want \"E%5BN%5Dx\" when \"f%28x%29=2%5Ex%2F10%5Ex\"; E, representing sigma, means the addition of all of the following. By E[N] I mean sigma of all N, positive integers. (E[n]{1,2,3.4,5}=8)
\n" ); document.write( "we're basically looking for all solutions for \"2%5Ex%2F10%5Ex\" given x=N (positive integer).
\n" ); document.write( "this can also be expressed as E[n]\"1%5Ex%2F5%5Ex\"; I can simplify it no further as of now.\r
\n" ); document.write( "\n" ); document.write( "Again, it is obvious the answer is 5/4 because it is the only choice over 1, an easy choice considering the question is 1+something.
\n" ); document.write( "I checked, and it really does equal 5/4; I just can't find how to get there :P
\n" ); document.write( "good luck and if u get the process email me ;) \n" ); document.write( "
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