document.write( "Question 1121015: The first three terms of an infinite geometric sequence are m−1, 6, m+4, where m∈ℤ
\n" ); document.write( "Write down an expression for the common ratio, r.
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Algebra.Com's Answer #736742 by greenestamps(13200) $\"\"$ $\"About$

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\n" ); document.write( "For three consecutive terms in a geometric sequence, the square of the middle term is equal to the product of the first and last:

\n" ); document.write( " $\"6%5E2+=+%28m-1%29%28m%2B4%29\"$
\n" ); document.write( " $\"m%5E2%2B3m-4+=+36\"$
\n" ); document.write( " $\"m%5E2%2B3m-40+=+0\"$
\n" ); document.write( " $\"%28m%2B8%29%28m-5%29+=+0\"$

\n" ); document.write( "m = -8 or m = 5; check to see which one(s) work

\n" ); document.write( "m = -8: the sequence is -9, 6, -4 -- geometric with common ratio -2/3
\n" ); document.write( "m = 5: the sequence is 4, 6, 9 -- geometric with common ratio 3/2 \n" ); document.write( "

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