document.write( "Question 607821: Please help me with problem, thanks:\r
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Algebra.Com's Answer #382919 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!

 
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document.write( "Hi
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document.write( "Geomtric sequence: 
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document.write( "{7+(-21)+63+(-189)+...}
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document.write( "Note the Change of sign:
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document.write( " 7/4(1-r^n) = 3829
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document.write( "  (1-(-)3^n) = (4/7)3829 = 2188
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document.write( "     3^n = 2187
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document.write( "       n = 7 \n" );
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