MTH-100 Lecture Notes - Logarithm, Binary Logarithm, Inverse Function
Document Summary
The logarithm is an inverse function to an exponential function. Suppose we want to find log 50 rewriting 2. We know y is between 5 and 6 because 25 = 32 and 26 =64. You might notice on your calculator that log appears with no base. When a log appears with no base present, the base is 10. Example 5. log 1000 = 3 since 103 = 1000. When the base is e, we use ln instead of log. This is called the natural log e is irrational. When we use the log button on a calculator we are asking 10 to what power gives us the number. When we use the ln button on a calculator we are asking e to what power gives us the number. Remember e can be estimated as 2. 72, so ln is asking 2. 72 to what power gives us the number.