5.2a Laws of Logarithms


5.2a Laws of Logarithms

  Law 1:   log a xy= log a x+ log a y   Example:   log 5 25x= log 5 25+ log 5 x   Beware!!   log a x+ log a y log a ( x+y )  
  Law 2:   log a ( x y )= log a x log a y     Example:   log 5 x 25 = log 5 x log 5 25   Beware!!   log a x y log a x log a y   
  Law 3:   log a x m =m log a x   Example:   log 5 y 5 =5 log 5 y   Beware!!    ( log a x ) 2 2 log a x