HP (Hewlett-Packard) NW280AAABA Calculator User Manual


 
332 Functions and commands
Differential
Equation
Returns the solution to a differential equation.
deSolve(Eq,[TimeVar],Var)
Example:
desolve(y''+y=0,y) returns G_0*cos(x)+G_1*sin(x)
ODE Solve Ordinary Differential Equation solver. Solves an ordinary
differential equation given by Expr, with variables declared in
VectrVar and initial conditions for those variables declared in
VectrInit. For example, odesolve(f(t,y),[t,y],[t0,y0],t1) returns
the approximate solution of y'=f(t,y) for the variables t and y
with initial conditions t=t0 and y=y0.
odesolve(Expr,VectVar,VectInitCond,Final
Val,[tstep=Val,curve])
Example:
odesolve(sin(t*y),[t,y],[0,1],2) returns
[1.82241255674]
Linear System Given a vector of linear equations and a corresponding
vector of variables, returns the solution to the system of linear
equations.
linsolve([LinEq1, LinEq2,…], [Var1,
Var2,…])
Example:
linsolve([x+y+z=1,x-y=2,2*x-z=3],[x,y,z])
returns [3/2,-1/2,0]
Rewrite
lncollect Rewrites an expression with the logarithms collected. Applies
ln(a)+n*ln(b) = ln(a*b^n) for an integer n.
lncollect(Expr)
Example:
lncollect(ln(x)+2*ln(y)) returns ln(x*y^2)
powexpand Rewrites an expression containing a power that is a sum or
product as a product of powers. Applies
a^(b+c)=(a^b)*(a^c).
powexpand(Expr)
Example:
powexpand(2^(x+y)) yields (2^x)*(2^y)