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having trouble writing a logarithmic expression as a single

Posted: Tue Jul 28, 2009 6:27 pm
Question: Write the logarithmic expression 3 log _2 X + log 2_2 Y - 5 log_2 Z as a single logarithm. Assume X anY are positive numbers. Thank YOU!!

Posted: Tue Jul 28, 2009 7:17 pm
Write the logarithmic expression 3 log _2 X + log 2_2 Y - 5 log_2 Z as a single logarithm.
Apply the multiplier-to-power log rule to move the multipliers 3 and 5 inside their respective logs. Then use the addition rule to combine the first two logs into one. Lastly, apply the subtraction log rule to combine this new log with the third log in the original expression.

You should end up with $\log_2\left(\frac{x^2 y}{z^5}\right)$, assuming the first "2" in the second term is a typo.

Re: having trouble writing a logarithmic expression as a single

Posted: Tue Jul 28, 2009 7:58 pm
thank you. yes it was a typo.