HP HP-20S - Page 112

Q. How do I clear all or portions of memory?
A. See page 12 to clear portions of memory. To clear all memory,
press and hold down [C], then press and hold down both and
[(Z+]. When you release them, all memory is cleared.
Q. What does an “E” in a number (for example, 2.51E—13) mean?
A. Exponent of ten (for example, 2.51 x 107 13). Refer to “Scientific
and Engineering Notation” on page 18.
Q. Why does calculating the sine of 7 radians display a very small
number instead of zero?
A. The calculator is not malfunctioning. = cannot be expressed exactly
with the 12-digit precision of the calculator.
Q. Why do I get incorrect answers when I use the trigonometric
functions?
A. You must make sure you are in the correct trigonometric mode
(page 34).
Q. What does PEND in the display mean?
A. An arithmetic operation is pending (in progress).
Q. What does : in the display mean?
A. The key has been pressed, or two values have been re-
turned (page 14).
110 Assistance, Batteries, Memory and Service