document.write( "Question 1032522: Hi, these questions are really confusing, could you please help me?\r
\n" ); document.write( "\n" ); document.write( "For problems 9 and 10, write each sum using summation notation.\r
\n" ); document.write( "\n" ); document.write( "9.2 + 5 + 8 + 11 + ... + 29\r
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\n" ); document.write( "\n" ); document.write( "10. 6 - 12 + 24 - 48 + ...\r
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\n" ); document.write( "\n" ); document.write( "11. Find the sum of the arithmetic sequence 2, 4, 6, 8, ..., 70.\r
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\n" ); document.write( "\n" ); document.write( "12. Find the sum of the geometric sequence
\n" ); document.write( "42,7,7/6,...,42,(1/6)^8
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\n" ); document.write( "\n" ); document.write( "For problems 13 and 14, find the sum of the first n terms of the sequence. The sequences are either arithmetic or geometric.\r
\n" ); document.write( "\n" ); document.write( "13. -1, 11, -121, ...; n = 9\r
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\n" ); document.write( "\n" ); document.write( "14. 14, 8, 2,...; n=9\r
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\n" ); document.write( "\n" ); document.write( "15. Determine whether the infinite series is equal to a real number. If so, find the sum.
\n" ); document.write( "\"+1%2F64+%2B+1%2F32+%2B+1%2F16+%2B+1%2F8+%2B+...+\"
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Algebra.Com's Answer #647179 by ikleyn(52776)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "11. Find the sum of the arithmetic sequence 2, 4, 6, 8, ..., 70.\r
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document.write( "On arithmetic progressions, read the lesson Arithmetic progressions in this site.\r\n" );
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document.write( "The given progression is AP with the first term 2 and the common difference 2.\r\n" );
document.write( "It contains all even integers between 2 and 70, inclusively.\r\n" );
document.write( "The number of the terms is \"70%2F2\" = 35.\r\n" );
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document.write( "Use the formula for the sum of an AP\r\n" );
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document.write( "S = \"%28%28a%5B1%5D%2Ba%5Bn%5D%29%2An%29%2F2\" = \"%28%282%2B70%29%2A35%29%2F2\".\r\n" );
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document.write( "Calculate it yourself.\r\n" );
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\n" ); document.write( "\n" ); document.write( "12. Find the sum of the geometric sequence 42, 7, 7/6,. . . , 42*(1/6)^8\r
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document.write( "The last term of the progression was written INCORRECTLY. I fixed it.\r\n" );
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document.write( "On geometric progressions, read the lesson Geometric progressions in this site.\r\n" );
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document.write( "The given progression is GP with the first term 42 and the common ratio \"1%2F6\".\r\n" );
document.write( "The number of the terms is 9.\r\n" );
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document.write( "Use the formula for the sum of a GP\r\n" );
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document.write( "S = \"a%5B1%5D%2A%28%28q%5En-1%29%2F%28q-1%29%29\" = \"42%2A%28%28%281%2F6%29%5En-1%29%2F%28%281%2F6%29-1%29%29%29\" = \"42%2A%28%28%281-6%5En%29%2A6%29%2F%286%5En%2A%281-6%29%29%29\" = \"42%2A%28%28%286%5En-1%29%2A6%29%2F%28%286-1%29%2A6%5En%29%29%29\" = \"%28%2842%2A6%29%2F5%29%2A%28%286%5En-1%29%2F6%5En%29\" = \"%28%2842%2A6%29%2F5%29%2A%28%286%5E9-1%29%2F6%5E9%29\".\r\n" );
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document.write( "Calculate it yourself.\r\n" );
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