100 ! Numerical differentiation 
110 DEF f(x)=sin(x)
120 LET h=0.00001
130 DEF g(x)=(f(x+h)-f(x))/h
140 SET WINDOW -2,6,-4,4
150 DRAW grid
160 SET POINT STYLE 1
170 FOR x=-2 TO 6 STEP 0.02
180    PLOT POINTS:x,g(x)
190 NEXT x
200 END
 