Goals:  Understand logarithms as the inverse of exponents  Convert between exponential and logarithmic forms  Evaluate logarithmic functions

Evaluate Logarithmic Expressions  A logarithmic function is the inverse of an exponential function  Given a y = x, a logarithm is defined as log a x = y  Examples: 2 4 = 16  log 2 16 = 4 log 2 8 = 3  2 3 = = 625  log = 4 log 7 49 = 2  7 2 = 49

Special Logarithmic Values  If a and b are >1, then log a 1 = 0 because a 0 = 1 log a a = 1 because a 1 = a log a a x = x because a x = a x