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Section 7
Mathematics and
Number-Alteration Functions
The HP 12C Platinum provides several keys for mathematical functions and for
altering, numbers. These functions are useful for specialized financial
calculations as well as for general mathematics calculations.
One-Number Functions
Most of the mathematics functions require that only one number be in the
calculator (that is, the number in the display) before the function key is pressed.
Pressing the function key then replaces the number in the display by the result.
Reciprocal. Pressing y calculates the reciprocal of the number in the display –
that is, it divides 1 by the number in the display.
Square. Pressing g’ calculates the square of the number in the display.
Square Root. Pressing gr calculates the square root of the number in the
display.
Logarithm. Pressing g¿ calculates the natural logarithm (that is, the
logarithm to the base e) of the number in the display. To calculate the common
logarithm (that is, the logarithm to the base 10) of the number in the display,
calculate the natural logarithm, then press 10g¿z.
Exponential. Pressing g> calculates the exponential of the number in the
display – that is, it raises the base e to the number in the display.
Factorial. Pressing ge calculates the factorial of the number in the display –
that is, it calculates the product of the integers from 1 to n, where n is the number
in the display.
Round. The display format specifies to how many decimal places a number
inside the calculator is rounded when it appears in the display; but the display
format alone does not affect the number itself inside the calculator. Pressing
fB, however, changes the number inside the calculator to match its
displayed version. Thus, to round a number in the display to a given number of
decimal places, temporarily set the display format (as described on page 71) to
show the desired number of decimal places, then press fB.
