document.write( "Question 149609: How would you solve: log(base 2x)+log(base 4x)+log(base 8x) = 1? \n" ); document.write( "
Algebra.Com's Answer #109750 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"log%282%2C%28x%29%29%2Blog%284%2C%28x%29%29%2Blog%288%2C%28x%29%29=1\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( " Use the Change of Base formula to rewrite each log. Remember, the Change of Base formula is: \"log%28b%2C%28x%29%29=log%2810%2C%28x%29%29%2Flog%2810%2C%28b%29%29\"\r
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\n" ); document.write( "\n" ); document.write( " Rewrite \"4\" as \"2%5E2\". Rewrite \"8\" as \"2%5E3\". \r
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\n" ); document.write( "\n" ); document.write( " Rewrite each log using the identity \"log%28b%2C%28x%5Ey%29%29=y%2Alog%28b%2C%28x%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "Now to make things simple, let \"z=log%2810%2C%282%29%29\". So this means that the equation is now\r
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\n" ); document.write( "\n" ); document.write( "Notice now that the LCD is 6z\r
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\n" ); document.write( "\n" ); document.write( " Multiply both sides by the LCD \"6z\" to clear the fractions.\r
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\n" ); document.write( "\n" ); document.write( "\"6%2Alog%2810%2C%28x%29%29%2B3%2Alog%2810%2C%28x%29%29%2B2%2Alog%2810%2C%28x%29%29=6z\" Distribute and multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"log%2810%2C%28x%29%29%286%2B3%2B2%29=6z\" Factor out the GCF \"log%2810%2C%28x%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"log%2810%2C%28x%29%29%2811%29=6z\" Add\r
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\n" ); document.write( "\n" ); document.write( "\"11%2Alog%2810%2C%28x%29%29=6z\" Rearrange the terms.\r
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\n" ); document.write( "\n" ); document.write( "\"log%2810%2C%28x%29%29=%286z%29%2F%2811%29\" Divide both sides by 11.\r
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\n" ); document.write( "\n" ); document.write( "\"log%2810%2C%28x%29%29=%286%2Alog%2810%2C%282%29%29%29%2F%2811%29\" Now replace \"z\" with \"log%2810%2C%282%29%29\".\r
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\n" ); document.write( "\n" ); document.write( "\"log%2810%2C%28x%29%29=%286%2F11%29%2Alog%2810%2C%282%29%29\" Rearrange the terms.\r
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\n" ); document.write( "\n" ); document.write( "\"log%2810%2C%28x%29%29%2Flog%2810%2C%282%29%29=6%2F11\" Divide both sides by \"log%2810%2C%282%29%29\".\r
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\n" ); document.write( "\n" ); document.write( "\"log%282%2C%28x%29%29=6%2F11\" Use the change of base formula to rewrite the left side.\r
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\n" ); document.write( "\n" ); document.write( " Rewrite the equation using the property: \"log%28b%2C%28x%29%29=y\" ====> \"b%5Ey=x\"\r
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\n" ); document.write( "\n" ); document.write( "So the answer is which approximates to \"x=1.45948\"
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