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?
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document.write( "a)1/25
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document.write( "b)1/4
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document.write( "c)1
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document.write( "d)5/4 \n" );
document.write( "
Algebra.Com's Answer #26488 by mszlmb(115)![]() ![]() 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= \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 \n" ); document.write( "or \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 \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( " Do you see the pattern, again, of *2 and *5? \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "we're basically looking for all solutions for \n" ); document.write( "this can also be expressed as E[n] \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 ;) |