document.write( "Question 771674: Show that [1/loga (abc)] + [1/logb (abc)] + [1/logc (abc)] = 1\r
\n" ); document.write( "\n" ); document.write( "My working:
\n" ); document.write( " [1/log abc/log a] + [1/log abc/log b] + [1/log abc/log c]
\n" ); document.write( "=[log a/log abc] + [log b/log abc] + [log c/log abc]
\n" ); document.write( "=[log (a*b*c)] / [log (abc)^3]
\n" ); document.write( "=log (abc) / log (abc)^3
\n" ); document.write( "=1/3
\n" ); document.write( "
\n" ); document.write( "My answer is is 1/3, it's wrong. I should prove that the answer is equals to 1. Please help me.
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Algebra.Com's Answer #470357 by KMST(5328)\"\" \"About 
You can put this solution on YOUR website!
\"1%2Flog%28a%2C%28abc%29%29\"+\"1%2Flog%28b%2C%28abc%29%29\"+\"1%2Flog%28c%2C%28abc%29%29=1\"
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\n" ); document.write( "Your working start is good:
\n" ); document.write( "\"1%2F%28%28log%28abc%29%2Flog%28a%29%29%29\" + \"1%2F%28%28log%28abc%29%2Flog%28b%29%29%29\" + \"1%2F%28%28log%28abc%29%2Flog%28c%29%29%29\"
\n" ); document.write( "=\"log%28%28a%29%29%2Flog%28%28abc%29%29\" + \"log%28%28b%29%29%2Flog%28%28abc%29%29\" + \"log%28%28c%29%29%2Flog%28%28abc%29%29\"
\n" ); document.write( "Then, you forget that you are adding fractions with a common denominator, and multiply the denominators instead of leaving the common denominator alone, and just adding the numerators,like this:
\n" ); document.write( "=\"%28log%28%28a%29%29%2Blog%28%28b%29%29%2Blog%28%28c%29%29%29%2Flog%28%28abc%29%29\"=\"log%28%28abc%29%29%2Flog%28%28abc%29%29\"=\"1\"
\n" ); document.write( "That kind of confusion happens to most of us now and then.
\n" ); document.write( "Unfortunately, once we make a mistake like that we cannot detect it by ourselves.
\n" ); document.write( "We need help from a pair of fresh, unbiased eyes.
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