document.write( "Question 1157839: given two terms in a geometric sequence find the term named in the problem and the explicit formula\r
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Algebra.Com's Answer #780794 by greenestamps(13203)\"\" \"About 
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\n" ); document.write( "#24....

\n" ); document.write( "For any geometric sequence,
\n" ); document.write( "\"a%28n%29+=+a%280%29%2Ar%5E%28n-1%29\"

\n" ); document.write( "The formula says exactly what the definition of a geometric sequence says: the n-th term is the first term, multiplied by the common ratio, r, (n-1) times.

\n" ); document.write( "Note it is (n-1) times, because the first term is multiplied by the common ratio 0 times.

\n" ); document.write( "\"a%285%29=48\"
\n" ); document.write( "\"a%284%29=24\"

\n" ); document.write( "Formally, divide a(5) by a(4):

\n" ); document.write( "\"a%285%29%2Fa%284%29+=+%28a%280%29r%5E4%29%2F%28a%280%29r%5E3%29+=+r\"
\n" ); document.write( "\"r+=+48%2F24+=+2\"

\n" ); document.write( "Informally, simply observe that the 5th term is the 4th term multiplied by the common ratio; 48/24 = 2.

\n" ); document.write( "We have determined r; to finish finding the explicit formula, we need to find a(0).

\n" ); document.write( "\"a%284%29+=+24+=+a%280%29r%5E3+=+a%280%292%5E3+=+8a%280%29\"
\n" ); document.write( "\"a%280%29+=+24%2F8+=+3\"

\n" ); document.write( "The explicit formula is
\n" ); document.write( "\"a%28n%29+=+3%282%5E%28n-1%29%29\"

\n" ); document.write( "Evaluate a(9) using the formula.

\n" ); document.write( "Or, informally, multiply the 5th term, 48, by 2, 4 more times....

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