HP 48gII Graphing Calculator Manual do Utilizador descarregar pdf (Página 486)

In the calculator use:

'd1y(x)+x^2*y(x)=5' ` 'y(x)' ` DESOLVE

The solution provided is {‘y =

(INT(5*EXP(xt^3/3),xt,x)+cC0)*1/EXP(x^3/3))’ }, i.e.,

The variable ODETYPE

You will notice in the soft-menu key labels a new variable called @ODETY

(ODETYPE). This variable is produced with the call to the DESOL function and

holds a string showing the type of ODE used as input for DESOLVE. Press

@ODETY to obtain the string “1st order linear”.

-- Solve the second-order ODE:

+ x (dy/dx) = exp(x).

In the calculator use:

‘d1d1y(x)+x*d1y(x) = EXP(x)’ ` ‘y(x)’ ` DESOLVE

The result is an expression having two implicit integrations, namely,

For this particular equation, however, we realize that the left-hand side of the

equation represents d/dx(x dy/dx), thus, the ODE is now written:

d/dx(x dy/dx ) = exp x,

x dy/dx = exp x + C.

.)3/exp(5)3/exp()(

cCdxxxxy +⋅⋅⋅−=

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HP 48gII Graphing Calculator Manual do Utilizador Página 486