HP 15c Manual

 Section 1: Getting Started 21 
 
 
Clearing Sequence Effect 
 ´ CLEAR M  
In Run mode: Repositions program memory to line 000. 
In Program mode: Deletes all program memory. 
 ´ CLEAR Q Clears all data storage registers. 
 ´ CLEAR u* Clears any prefix from a partially entered 
key sequence. 
* Also temporarily displays the mantissa. 
Display Clearing: ` and − 
The HP-15C has two types of display clearing operations: ` (clear X) 
and − (back arrow). 
In Run mode:  
 ` clears the display to zero. 
 −...

22 Section 1: Getting Started 
 
Calculations 
One-Number Functions 
A one-number function performs an operation using only the number in the 
display.  To  use  any  one-number  function,  press  the  function  key after the 
number has been placed in the display. 
Keystrokes Display 
45 45 
|o 1.6532 
Two-Number Functions and v 
A  two-number  function  must  have  two  numbers  present  in  the  calculator 
before executing  the  function. +, -, * and ÷ are  examples  of 
two-number functions....

 Section 1: Getting Started 23 
 
Example: Calculate (9 + 17  4) ÷ 4. 
Keystrokes Display  
9 v 9.0000 Digit entry terminated. 
17 + 26.0000 (9 + 17). 
4 - 22.0000 (9 + 17 –=4)K=
4 ÷ 5.5000 (9 + 17 –=4) 

 
24 
Section 2 
Numeric Functions 
This  section  discusses  the  numeric  functions  of  the  HP-15C  (excluding 
statistics  and  advanced  functions).  The  nonnumeric  functions  are  discussed 
separately  (digit  entry  in  section  1,  stack  manipulation  in  section  3,  and 
display control in section 5). 
The  numeric  functions  of  the  HP-15C  are  used  in  the  same  way  whether 
executed from the keyboard or in a program. Some of the functions (such as 
a) are, in fact, primarily of...

 Section 2: Numeric Functions 25 
 
Keystrokes Display  
123.4567 |‘  123.0000  
|K “ |‘ -123.0000 Reversing the sign does 
not alter digits. 
|K ´q -0.4567  
1.23456789 “   
|& -1.2346  
´ CLEAR u 
(release) 
 1234600000 Temporarily displays all 
-1.2346 digits in the mantissa. 
|a  1.2346  
One-Number Functions 
One-number math functions in the HP-15C operate only upon the number in 
the display (X-register). 
General Functions 
Reciprocal. Pressing ∕ calculates  the  reciprocal  of  the  number  in...

26 Section 2: Numeric Functions  
 
Trigonometric Operations 
Trigonometric  Modes. The  trigonometric  functions  operate  in  the 
trigonometric  mode  you  select.  Specifying  a  trigonometric  mode  does  not 
convert  any  number already  in  the  calculator  to  that  mode;  it  merely  tells 
the  calculator  what  unit  of  measure  (degrees,  radians,  or  grads)  to  assign  a 
number for a trigonometric function. 
Pressing | D sets  Degrees  mode.  No  annunciator  appears  in  the 
display....

 Section 2: Numeric Functions 27 
 
Hours.Decimal Hours  Hours.Minutes Seconds Decimal Seconds 
(H.h)  (H.MMSSs) 
Degrees.Decimal Hours  Degrees.Minutes Seconds Decimal Seconds 
(D.d)  (D.MMSSs) 
Hours/Degrees-Minutes-Seconds  Conversion. Pressing ´ h 
converts  the  number  in  the  display  from  a  decimal  hours/degrees  format  to 
an hours/degree-minutes-seconds-decimal seconds format. 
For example, press ´ h to convert 
 
Press ´ u to display the value to all possible decimal places: 
 
Decimal...

28 Section 2: Numeric Functions  
 
Logarithmic Functions 
Natural  Logarithm. Pressing |Z calculates  the  natural  logarithm  of 
the number in the display; that is, the logarithm to the base e. 
Natural  Antilogarithm. Pressing  calculates  the  natural  antilogarithm 
of the number in the display; that is, raises e to the power of that number. 
Common  Logarithm. Pressing | o calculates  the  common 
logarithm of the number in the display; that is, the logarithm to the base 10. 
Common...

 Section 2: Numeric Functions 29 
 
Two-Number Functions 
The HP-15C performs two-number math functions using two values entered 
sequentially  into  the  display.  If  you  are keying  in both  numbers,  remember 
that  they  must  be  separated  by v or  any  other  function – like | 
‘ or ∕ – that terminates digit entry. 
For a two-number function, the first value entered is considered the y-value 
because  it  is  placed  into  the  Y-register  for  memory  storage.  The  second 
value  entered  is...

30 Section 2: Numeric Functions  
 
For example, to find the sales tax at 3% and total cost of a $15.76 item: 
Keystrokes Display  
15.76 v 15.7600 Enters the base number (the price). 
3 |k 0.4728 Calculates 3% of $15.76 (the tax). 
+ 16.2328 Total cost of item ($15.76 + $0.47). 
Percent  Difference. The ∆ function  calculates  the  percent difference 
between two  numbers. The  result expresses the  relative  increase  (a  positive 
result)  or  decrease  (a  negative  result)  of  the  second  number...