# Writing Programs For Solve - HP -32S Owner's Manual

Rpn scientific calculator.

To solve for a different unknown in the same equation: Just
specify the unknown variable: flj| solve// I {SOLVE} variable. The
same program that was last specified (FN= label) will be used again.
Writing Programs for SOLVE
Before you solve for an unknown variable, you must write a program
or subroutine that evaluates the function.*
Writing a Function From an Equation. First simplify the equation
by combining all like variables and all constants. Then move all the
terms to one side of the equation, leaving only zero on the other side.
For example, the equation for the volume of a box is given by
Length x Width x Height = Volume.
Rearranging the terms to make one side equal to zero yields
Length x Width x Height - Volume = 0 , or
L x W x H - V * =
0.
To write a program evaluating a function:
1. Begin with a label so that the program can be called by SOLVE.
2. Include an INPUT instruction for each variable, including the
unknown. (If there is only one variable in the function, omit the
INPUT instruction since it is ignored for the unknown anyway.)t
* SOLVE worksonly with real numbers. However, if you have a complex-valued function that
canbe written to isolate the real and imaginary parts, SOLVE canthen solve for the parts
separately.
tThe INPUT instructions are useful for multi-variable functions. Since the INPUT for the
unknown is ignored, you need write only one program, which contains INPUT instructions
for all variables. You can use the same programno matter which variable is the unknown.
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7: Solving ffor an Unknown Variable in an Equation  