The second Key on your calculator is the natural log key or ln which is 
		log, base e

		(e is an irrational number equal to approximately 2.718).  Natural logs are 
		written ln250 and means loge250=5.52 
		

		Example 1
		Find the natural logarithms to 4 decimal places.

		a) ln(9.25)= 2.2246
		b) ln(12.05)= 2.4891
		c) ln(0.013)= -4.3428
		d) ln(.5)= -.6931

	
		On your calculator, you can also "undo" the ln function.  "Undoing" a ln is
		called "finding the antilog".


		If you were given ln(x) = 1.3 then x = inverse natural log of 1.3 or the natural
		antilog of 1.3 or 
		x = e1.3=3.669


		You should be able to get natural antilogs or inverse natural logs using
		2nd ln or inv ln or ex key.

		
		Example 2
		Find the natural antilog to 4 decimal places.


		a) ln(x)= -3.5
		   x= .0302

		b) ln(x)= .09
		   x= 1.094

		c) ln(x)= 4.75
		   x= 115.58

		d) ln(x)= -.22
		   x= .8025


		Logs to other bases: Your calculator will evaluate common logs (base 10)
		and natural logs (base e).


		For other bases, use on of the following conversions.

		logbx = (logax)/(logab) = ln(x)/ln(b)
		
	
		Example 3
		log8250


		Method 1: Rewrite using comon logs and evaluate.
				log8250 = (log 250)/(log 8) = 2.655


		Method 2: Rewrite using natural logs and evaluate.
				log8250 = (ln 250)/(ln 8) = 2.655
		
		
		
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	Copyright © 1996 by B. Chambers and P. Lowry. All Rights	Reserved.