Solving ODEs That Are in Quadrature Format
Description
Examples
An ODE is said to be in quadrature format when the following conditions are met:
1) the ODE is of first order and the right hand sides below depend only on x or y(x):
quadrature_1_x_ode := diff(y(x),x)=F(x);
quadrature_1_x_ode≔ⅆⅆxy⁡x=F⁡x
quadrature_1_y_ode := diff(y(x),x)=F(y(x));
quadrature_1_y_ode≔ⅆⅆxy⁡x=F⁡y⁡x
2) the ODE is of high order and the right hand side depends only on x. For example:
quadrature_h_x_ode := diff(y(x),x,x,x,x)=F(x);
quadrature_h_x_ode≔ⅆ4ⅆx4y⁡x=F⁡x
where F is an arbitrary function. These ODEs are just integrals in disguised format, and are solved mainly by integrating both sides.
with⁡DEtools,odeadvisor,symgen
odeadvisor,symgen
odeadvisor⁡quadrature_1_x_ode
_quadrature
dsolve⁡quadrature_1_x_ode
y⁡x=∫F⁡xⅆx+c__1
odeadvisor⁡quadrature_1_y_ode
dsolve⁡quadrature_1_y_ode
x−∫` `y⁡x1F⁡_aⅆ_a+c__1=0
From the point of view of their symmetries, all ODEs "missing y" have the symmetry [xi = 0, eta = 1], and all ODEs "missing x" have the symmetry [xi = 1, eta = 0] (see symgen);
symgen⁡quadrature_1_x_ode
_ξ=0,_η=1
symgen⁡quadrature_1_y_ode
_ξ=1,_η=0
See Also
DEtools
odeadvisor
dsolve
quadrature
linear
separable
Bernoulli
exact
homogeneous
homogeneousB
homogeneousC
homogeneousD
homogeneousG
Chini
Riccati
Abel
Abel2A
Abel2C
rational
Clairaut
dAlembert
sym_implicit
patterns
odeadvisor,types
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