HP 50g Graphing Calculator - Manual (Page 232)

Page 6-26
The SOLVE soft menu
The SOLVE soft menu allows access to some of the numerical solver functions
through the soft menu keys. To access this menu use in RPN mode: 74 MENU,
or in ALG mode: MENU(74). Alternatively, you can use ‚(hold) 7 to
activate the SOLVE soft menu. The sub-menus provided by the SOLVE soft menu
are the following:
The ROOT sub-menu
The ROOT sub-menu include the following functions and sub-menus:
Function ROOT
Function ROOT is used to solve an equation for a given variable with a starting
guess value. In RPN mode the equation will be in stack level 3, while the
variable name will be located in level 2, and the initial guess in level 1. The
following figure shows the RPN stack before and after activating function
@ROOT:
In ALG mode, you would use ROOT(‘TAN( θ)=θ’,’θ’,5) to activate function ROOT:
Variable EQ
The soft menu key @@EQ@@ in this sub-menu is used as a reference to the variable
EQ. Pressing this soft menu key is equivalent to using function RCEQ (ReCall
EQ).
The SOLVR sub-menu
The SOLVR sub-menu activates the soft-menu solver for the equation currently
stored in EQ. Some examples are shown next: