For Advanced Information - HP -15C Owner's Handbook Manual

258 Appendix E: A Detailed Look at

Press | K to view the current approximation. If you want to
3.
continue calculating the final approximation, press − +
¦. This refills the stack with the current x-value and restarts
the calculator.

For Advanced Information

The HP-15C Advanced Functions Handbook explores more esoteric aspects
of f and its applications. These topics include:

Accuracy of the function to be integrated.

Shortening calculation time.

Calculating difficult integrals.

Using f in Complex mode.
If any other program line is displayed, return to Run mode
and single-step (Â) through the program until you
reach a n instruction (keycode 43 32) or line 000 (if
there is no n). (Be sure to hold the  key down
long enough to view the program line numbers and
keycodes.)
f