## 5 Reputation

13 years, 287 days

## Problem in solving differential equation...

Maple 12

Hi I want to solve the following equation. For this I have written the following program. But Maple showing error.

eq := diff(x(t), `\$`(t, 2))+326.1*(diff(x(t), `\$`(t, 1)))+3190*(diff(x(t), `\$`(t, 1)))^2-37500*sqrt(x(t)*(0.165e-2-x(t)))+2.825

ICs := x(0), Dx(0)-0

sol := dsolve({ICs, eq}, {x(t)}, type = numeric);

but it is showing

Error, (in dsolve/numeric/process_input) system must be entered as a set/list of expressions/equations

## Solving Differential equation with given...

Maple 13

I am trying to solve the the differential equation. for this I have written the following program. But it is showing the error.

restart

with(plots)

eq := diff(x(t), `\$`(t, 2))+326.1*(diff(x(t), `\$`(t, 1)))+3190*(diff(x(t), `\$`(t, 1)))^2-37500*sqrt(x(t)*(0.165e-2-x(t)))+2.825

BCs := [x(0), x(0.2e-1)-0.15e-2]

sol := dsolve({BCs, eq}, {x(t)}, type = numeric)

Maple is saying:

Error, (in dsolve/numeric/process_input) system...

## Problem in solving the differential equa...

Maple 12

can any body help me?

i want to solve the following differential equation

d2x(t)/dt- 0.066405*sqrt((x(t))(2*r-x(t)))+0.00042105*dx(t)/dt

﻿﻿﻿

for this I ahve written the following program

restart

with(plots)

eq := diff(x(t), `\$`(t, 2))-0.66405e-1*sqrt((x(t))(2*r-x(t)))+0.42105e-3*(diff(x(t), `\$`(t, 1)))

pars := {r = 1}

eq := subs(pars, eq)

## solving a differential equation...

Maple 13

How can I solve the following differential equation?

with plots

Eq[1]:=diff(f(eta),eta\$3)+g(eta);

Eq[2] := (diff(g(eta), `\$`(eta, 2)))/Pr+f(eta)*(diff(g(eta), eta));

BCs := [f(0), (D(f))(0), (diff(f(eta), `\$`(eta, 2)))(2), g(0)-1, g(2)]

pars := {Pr = 1}

for i to 2 do eq[i] := subs(pars, Eq[i]) end do

eqs := eq[1], eq[2]

vars := f(eta), g(eta)

bcs := op(subs(pars, BCs))

sol := dsolve({bcs, eqs}, {vars}, type = numeric, output = array...

## Coupled differential equation...

Maple 13

Can I solve the following two coupled differential equations instead of the previous one in Maple 13?

with plots

Eq[1]:=3*f(eta)*(diff(f(eta), `\$`(eta, 2)))-2*(diff(f(eta), eta))^2+3*g(eta)

Eq[2]:=(diff(g(eta), `\$`(eta, 2)))/Pr+f(eta)*(diff(g(eta), eta))

BCs := [f(0), (D(f))(0), g(0)-1, g(25)]

pars := {Pr = 1}

for i to 2 do eq[i] := subs(pars, Eq[i]) end do

eqs := eq[1], eq[2]

vars := f(eta), g(eta)

 1 2 3 4 5 Page 4 of 5
﻿