HP 50g manual Chapter Differential Equations, CALC/DIFF menu, Function Ldec

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-1[F(s)] = f(t)
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. This function requires you to provide two pieces of input:

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