document.write( "Question 309476: The question is:
\n" ); document.write( "The nth term of a sequence is 4/n^2
\n" ); document.write( "(a)Write down the first three terms of the sequence, expressing each term in its simplest form.\r
\n" ); document.write( "\n" ); document.write( "(b)The kth term in the sequence is 1/100
\n" ); document.write( "Find the value of k
\n" ); document.write( "Note: it is K not N\r
\n" ); document.write( "\n" ); document.write( "(c)Given that the nth term of the sequence is less than 0.0064, find the smallest value of n. '\r
\n" ); document.write( "\n" ); document.write( "I shall be highly glad if you help me.
\n" ); document.write( "Regards,
\n" ); document.write( "Benjamin.
\n" ); document.write( "

Algebra.Com's Answer #221396 by alicealc(293)\"\" \"About 
You can put this solution on YOUR website!
(a)
\n" ); document.write( "n = 1 -> 4/1^2 = 4/1 = 4
\n" ); document.write( "n = 2 -> 4/2^2 = 4/4 = 1
\n" ); document.write( "n = 3 -> 4/3^2 = 4/9 \r
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\n" ); document.write( "\n" ); document.write( "(b)
\n" ); document.write( "n = k -> 4/k^2 = 1/100
\n" ); document.write( "4*100 = k^2
\n" ); document.write( "400 = k^2
\n" ); document.write( "\"k+=+sqrt%28400%29\"
\n" ); document.write( "k = 20\r
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\n" ); document.write( "\n" ); document.write( "(c)
\n" ); document.write( "4/n^2 < 0.0064
\n" ); document.write( "4/0.0064 < n^2
\n" ); document.write( "625 < n^2
\n" ); document.write( "0 < n^2 - 625
\n" ); document.write( "0 < (n - 25)*(n + 25)
\n" ); document.write( "n = 25 or n = -25\r
\n" ); document.write( "\n" ); document.write( "++ -- ++
\n" ); document.write( "--o--o---
\n" ); document.write( "-25 25
\n" ); document.write( "*if n = 0 then 0^2 - 625 = -625 -> it gives the negative result for n = 0
\n" ); document.write( "because n = 0 is between -25 and 25, so the area between -25 and 25 will give negative result for the equation, and the left side and the right side of that area will give positive result
\n" ); document.write( "*because the equation should make result that is greater than 0 (>0) so the solution set for that inequality is the area that gives positive result.
\n" ); document.write( "so, n < -25 or n > 25\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "because n should not be negative number, the smallest value of n so that the nth term of the sequence is less than 0.0064 is 26 (the first integer that is greater than 25)
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