Here's how you can use these in Calculus to make your life a lot easier:

Check this guy out:

Ln( ( xwz ) / ( y^2 ) )  ...  This is a bit of a mess.
 

Having logs of little things will be much easier, so let's use our rules:


Ln( ( xwz ) / ( y^2 ) )  =  Ln( xwz ) - Ln( y^2 )  ...  rule 2  ...  =  Ln( x ) + Ln( w ) + Ln( z ) - 2 * Ln( y )  ...  the addition was rule 1  ...  the subtraction is rule 3  ...  Done!
 

Trust me on this -- the Calculus on this would take about 10 seconds!

Let's do another one:


log( ( x^2 w ) / ( y z^3 ) )  =  log( x^2 w ) - log( y z^3 )  ...  rule 2  ...  =  log( x^2 ) + log( w ) - ( log( y ) + log( z^3 ) )  ...  both parts were rule 1  ...  Be careful with the minus sign  ...  = 2 * log( x ) + log( w ) - log( y ) - 3 * log( z )  ...  the first part and the last part are rule 3  ...  I distributed the " - "