NUMINT on the TI-92's and TI-89s

To type in this program first push the "Apps" button on your keyboard. Next go to "7 Program Editor" and then "3 New". A placard will appear and you want "Program" (rather than function), then "main->" and then type "numint" into the textbox provided for variable. This is the name of the program. Now hit your "Enter" button and the Program Editor will allow you to type in the program below one line at a time. You can save typing time by using the "catalog" button and selecting the term you need.

Functions in your catalog are printed in red. The arrow symbol (->) is in your catalog, but is also the STO button on the keyboard. Similarly, double quotes (") is a catalog symbol, but is also on your keyboard.

The TI-92 will convert upper case letters to lower case; I've list the "L" as an upper case only to distinguish it from the number "1"

To run the program, type "numint()" into your home window, then hit the "ENTER" key on the keyboard.

numint()
Prgm
y1(x) ->y
Clr IO
DelVar a,b,n,x,t,h,m,L,j
Input "lower = ", a
Input "upper = ",b
Input "number of intervals = ", n
(b-a)/(2*n) -> h
0->L
0->m
1->j
a->x
While j<n+1
L+y1(x) ->L
x+h->x
m+y1(x) ->m
x+h->x
j+1->j
EndWhile
2*L*h->L
Disp "Left Sum = ", approx(L)
L+2*h*y1(x) ->t
a->x
t-2*h*y1(x)->t
Disp "Right Sum = ", approx(t)
(L+T)/2->t
Disp "Trapezoid Sum = ", approx(t)
Pause
2*h*m->m
Disp "Midpoint Sum =", approx(m)
(2*m+t)/3->m
Disp "Simpsons Rule = ", approx(m)
DelVar a,b,n,x,t,h,m,L,j
EndPrgm