HP Prime Graphing Calculator - Manual (Page 125)

Function app 121
2. Specify the start
value for x:
Tap
and
press Q 1 . 3
E .
3. Tap .
4. Select the other
function as the
boundary for the
integral. (If F1(X) is
the currently
selected function,
you would choose
F2(X) here, and vice
versa.)
5. Specify the end value for x:
Tap and press 2 . 3 E .
The cursor jumps to
x = 2.3 and the
area between the
two functions is
shaded.
6. To display the
numerical value of
the integral, tap
.
7. Tap to return
to the Plot menu.
Note that the sign of
the area calculated
depends both on which function you are tracing and
whether you enter the endpoints from left to right or
right to left.
Shortcut : When the Goto option is available, you can
display the Go To screen simply by typing a number. The