document.write( "Question 1095389: Hello. I needed some help with explicit and recursive rules. I do not understand how to write one of these rules when asked to on a worksheet. If you can, please describe this to me step by step. (I just started Algebra I) \n" ); document.write( "

Algebra.Com's Answer #709908 by ikleyn(52781) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "The recursive formula usually expresses the current term via the preceding one.\r
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\n" ); document.write( "\n" ); document.write( "So, the recursive formula for the current term refers to the preceding term.\r
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\n" ); document.write( "\n" ); document.write( "In opposite, the explicit formula expresses the current term directly, without the reference to the preceding term.\r
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document.write( "1.  Consider an arithmetic progression.\r\n" );
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document.write( "             I assume you know what it is.\r\n" );
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document.write( "    The recursive formula for the (n+1)-th term is   = .\r\n" );
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document.write( "    It express the next term via the preceding one.\r\n" );
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document.write( "    The explicit formula for (n+1)-th term is  = .\r\n" );
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document.write( "2.  Similarly for an geometric progression.\r\n" );
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document.write( "             I assume you know what it is.\r\n" );
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document.write( "    The recursive formula for the (n+1)-th term is   = .\r\n" );
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document.write( "    It express the next term via the preceding one.\r\n" );
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document.write( "    The explicit formula for (n+1)-th term is  = .\r\n" );
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\n" ); document.write( "\n" ); document.write( "------------
\n" ); document.write( "On arithmetic progression see introductory lessons\r
\n" ); document.write( "\n" ); document.write( "    - Arithmetic progressions\r
\n" ); document.write( "\n" ); document.write( "    - The proofs of the formulas for arithmetic progressions \r
\n" ); document.write( "\n" ); document.write( "    - Problems on arithmetic progressions \r
\n" ); document.write( "\n" ); document.write( "    - Word problems on arithmetic progressions\r
\n" ); document.write( "\n" ); document.write( "in this site.\r
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\n" ); document.write( "\n" ); document.write( "On geometric progressions see introductory lessons\r
\n" ); document.write( "\n" ); document.write( "    - Geometric progressions\r
\n" ); document.write( "\n" ); document.write( "    - The proofs of the formulas for geometric progressions \r
\n" ); document.write( "\n" ); document.write( "    - Problems on geometric progressions\r
\n" ); document.write( "\n" ); document.write( "    - Word problems on geometric progressions\r
\n" ); document.write( "\n" ); document.write( "in this site.\r
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