document.write( "Question 1186990: log2(x) + log2(x+1) = 1\r
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Algebra.Com's Answer #817945 by ikleyn(52781) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "I assume that the logarithms are base 2.\r\n" );
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document.write( "From\r\n" );
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document.write( "    log2(x) + log2(x+1) = 1\r\n" );
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document.write( "we have, using the property of logarithms,\r\n" );
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document.write( "    x*(x+1) = 2\r\n" );
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document.write( "Making FOIL, you get\r\n" );
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document.write( "    x^2 + x - 2 = 0.\r\n" );
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document.write( "Factor \r\n" );
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document.write( "   (x+2)*(x-1) = 0.\r\n" );
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document.write( "We deny the negative root x= -2, since it does not work under logarithm.\r\n" );
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document.write( "The only remaining solution is x= 1.    ANSWER\r\n" );
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