Chapter 14 - Differential Equations; The Calc/Diff Menu; Solution To Linear And Non-Linear Equations; Function Ldec - HP 50g User Manual

Chapter 14
Differential Equations
In this Chapter we present examples of solving ordinary differential
equations (ODE) using calculator functions. A differential equation is an
equation involving derivatives of the independent variable. In most cases,
we seek the dependent function that satisfies the differential equation.

The CALC/DIFF menu

The DIFFERENTIAL EQNS.. sub-menu within the CALC ( „Ö ) menu
provides functions for the solution of differential equations. The menu is
listed below with system flag 117 set to CHOOSE boxes:
These functions are briefly described next. They will be described in more
detail in later parts of this Chapter.
DESOLVE: Differential Equation SOLVEr, solves differential equations,
when possible
ILAP:
Inverse LAPlace transform, L
LAP: LAPlace transform, L[f(t)]=F(s)
LDEC: Linear Differential Equation Command

Solution to linear and non-linear equations

An equation in which the dependent variable and all its pertinent
derivatives are of the first degree is referred to as a linear differential
equation. Otherwise, the equation is said to be non-linear.

Function LDEC

The calculator provides function LDEC (Linear Differential Equation
Command) to find the general solution to a linear ODE of any order with
constant coefficients, whether it is homogeneous or not.
requires you to provide two pieces of input:
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[F(s)] = f(t)
This function