HP (Hewlett-Packard) 12C Manuale Utente

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18  Section 1: Getting Started 
 
File name: hp 12c pt_user's guide_English_HDPMF123E27  Page: 18 of 275 
Printed Date: 2005/8/1   
Dimension: 14.8 cm x 21 cm 
 
Keying in Large Numbers 
Since the display cannot show more than 10 digits of a number, numbers greater 
than 9,999,999,999 cannot be entered into the display by keying in all the digits 
in the number. However, such numbers can be easily entered into the display if the 
number is expressed in a mathematical shorthand called “scientific notation.” To 
convert a number into scientific notation, move the decimal point until there is only 
one digit (a nonzero digit) to its left. The resulting number is called the “mantissa” 
of the original number, and the number of decimal places you moved the decimal 
point is called the “exponent” of the original number. If you moved the decimal 
point to the left, the exponent is positive; if you moved the decimal point to the 
right (this would occur for numbers less than one), the exponent is negative. To key 
the number into the display, simply key in the mantissa, press Æ (enter exponent), 
then key in the exponent. If the exponent is negative, press Þ after pressing 
Æ. 
For example, to key in $1,781,400,000,000, we move the decimal point 12 
places to the left, giving a mantissa of 1.7814 and an exponent of 12: 
Keystrokes Display 
 
1.7814Æ12 
1.7814  12 
1,781,400,000,000 entered 
in scientific notation. 
Numbers entered in scientific  notation  can  be  used  in  calculations  just  like  any 
other number. 
Backspacing 
While you are entering a number, pressing gÚ deletes the last character you 
entered. After performing a calculation, pressing gÚ deletes the current 
number. 
Keystrokes 
(RPN mode) 
Display 
 
12345gÚgÚ 
.63\ 
 
123.63 
 
Correcting removes the 4 and 
5. gÚ clears the most recent 
digit entered. 
5+ 
128.63 
 
gÚ 
0.00 
Clears the calculator line.