HP (Hewlett-Packard) 50g ユーザーズマニュアル

Page 16-4

     

These functions are briefly described next.  They will be described in more detail 
in later parts of this Chapter.

DESOLVE:  Differential Equation SOLVEr, provides a solution if possible

ILAP: Inverse LAPlace transform, L

-1

[F(s)] = f(t)

LAP:  LAPlace transform, L[f(t)]=F(s)
LDEC: solves Linear Differential Equations with Constant coefficients, including 
systems of differential equations with constant coefficients

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.   Examples of linear differential equations 
are:  d

2

x/dt

2

 + 

β⋅(dx/dt) + ω

o

⋅x = A sin ω

f

 t, and 

∂C/∂t + u⋅(∂C/∂x) = D⋅(∂

2

C/

∂x

2

).

An equation whose right-hand side (not involving the function or its derivatives) 
is equal to zero is called a homogeneous equation.  Otherwise, it is called non-
homogeneous.  The solution to the homogeneous equation is known as a 
general solution.  A particular solution is one that satisfies the non-
homogeneous equation.

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:

•

the right-hand side of the ODE

•

the characteristic equation of the ODE