HP 39gs Master Manual page 76

Suppose we want to find the area between f x − 2 and
( ) = x
2
( ) 0.5x −1 from x = -2 to the first positive intersection of the two
g x =
graphs.
From the hand shaded screenshot shown above right it can be seen that
to find the area we need to split it into two sections, with the boundaries
being -2 and the two intersections.
After finding the first intersection using
Intersection we change into the view and
HOME
store the results into memory variable .
A
We then do the same thing for the second
intersection, storing the result into .
B
f − f
We can now calculate the area in the view, using for
HOME
1 2
− f
the first and for the second. Use to duplicate the first
f
2 1
integral and edit it to adjust the functions and limits.
Finally, the two solutions and add them to give the final answer.
76