fx-82MS fx-82TL fx-9860GII TI-83
LN
On a TI calculator you can calculate natural logarithms
LN
or via the CATALOG as
CATALOG ⎵ 2nd 0 ►ln( ENTER
Example 1
To calculate ln (1) = 0
LN 1 ENTER ln(1 0
Example 2
To calculate ln (e) = 1
e M LN 2nd ÷ ENTER ln(e 1
Example 3
To calculate ln (e2) = 2 × ln (e) = 2 × 1 = 2
e x S LN 2nd LN 2 ENTER ln(e^(2 2
Example 4
To calculate ln (√7) = 0.97295...
√ I LN 2nd x² 7 ENTER ln(√(7 .9729550745
and also ln (√7) = ½ ln (7) = 0.97295...
LN 7 ) ÷ 2 ENTER ln(7)/2 .9729550745
Example 5
To calculate eln (7) = 7
e x S 2nd LN LN 7 ENTER e^(ln(7 7
and this demonstrates the definition of the logarithm.
Example 6
To calculate the principle value of ln (-1) = πi = 3.141592654i in rectangular form (a+bi mode)
LN (–) 1 ENTER ln( -1 3.141592654i
or as ln (-1) = 3.141592654e1.570796327i in polar form (re^θi mode)
LN (–) 1 ENTER ln( -1 3.141592654e^1…
Details
The functions ln and ex are on the same key. This makes sense because these functions all deal with the number e.