document.write( "Question 1021048: For each sequence, find a closed formula for the general term, a sub n.\r
\n" ); document.write( "\n" ); document.write( "a) -2,-8,-18,-32,-50\r
\n" ); document.write( "\n" ); document.write( "b)96,94,92,90,88\r
\n" ); document.write( "\n" ); document.write( "c)-58,-580,-5800,-58000,-580000
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Algebra.Com's Answer #636830 by robertb(5830)\"\" \"About 
You can put this solution on YOUR website!
a) \"a%5Bn%5D+=+-2n%5E2\", which can be verified directly for n = 1, 2, 3, 4, 5...\r
\n" ); document.write( "\n" ); document.write( "b) This is an arithmetic sequence, so the general nth formula is \"a%5Bn%5D+=+a%5B1%5D%2B%28n-1%29d\", with \"a%5B1%5D+=+96\" and d = -2
\n" ); document.write( "==> \"a%5Bn%5D+=+96+-2%28n-1%29+=+98-2n\" for n = 1, 2, 3, 4, 5...\r
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\n" ); document.write( "\n" ); document.write( "c) This is a geometric sequence, where \"a%5Bn%5D+=+-58%2A10%5E%28n-1%29\" for n = 1, 2, 3, 4, 5...
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