document.write( "Question 309476: The question is:
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document.write( "The nth term of a sequence is 4/n^2
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document.write( "(a)Write down the first three terms of the sequence, expressing each term in its simplest form.\r
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document.write( "(b)The kth term in the sequence is 1/100
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document.write( "Find the value of k
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document.write( "Note: it is K not N\r
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document.write( "(c)Given that the nth term of the sequence is less than 0.0064, find the smallest value of n. '\r
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document.write( "I shall be highly glad if you help me.
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document.write( "Regards,
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document.write( "Benjamin. \n" );
document.write( "
Algebra.Com's Answer #221396 by alicealc(293)![]() ![]() ![]() 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 \n" ); document.write( " \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( " \n" ); document.write( "k = 20\r \n" ); document.write( " \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) \n" ); document.write( " |