base e (natural logarithms),
base 10, and
base b other than e or 10, where 0 < b
and b 
1.
1.Logarithms
We consider logarithms with three different bases:
base e (natural logarithms),base 10, andbase b other than e or 10, where 0 < b and b
Recall that the domain of a logarithm function consists of all real numbers x > 0.
Press MENU 1 to select the RUN-MAT screen.
Base e
Simply
use the ln (natural logarithm) key. For example, to calculate ln(17), press
ln 1 7 ) EXE
Base 10
Simply
use the log (common logarithm) key. For example, to calculate log(17),
press
log 1 7 ) EXE
Other Bases
For
logarithmic bases other than e or 10, one must apply the change of base
formula to convert to base e:
Hence, to determine log5(17), note that log5(17) = ln(17)/ln(5).
Here, log5(17) 
1.76.
