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In order to enter the exponential function, tex2html_wrap_inline212 , in Maple, you must use the exp command. The syntax of this command is similar to that of sin and cos. For example, here we enter the function tex2html_wrap_inline214 and then evaluate at x = 2.

  > f:=exp(x);


  > evalf(subs(x=2,f));


The natural log function, ln, is also used in this manner.

  > g:=ln(x);


  > evalf(subs(x=2,g));


Plotting the two functions tex2html_wrap_inline214 and tex2html_wrap_inline220 on the same coordinate system gives an idea of the symmetry around the line y=x. Make sure that you can identify which curve is tex2html_wrap_inline212 and which curve is tex2html_wrap_inline226 .

  > plot(f,g,x,x=-5..5,y=-5..5);

Looking at the graph of the two functions, you can get a pretty good idea of what happens to f(x) as x approaches negative infinity; however,in order to be sure, you must take a limit.

  > limit(f,x=-infinity);


Roxanne Tisch
Tue Sep 24 13:59:38 EDT 1996