Solving a Second Order Piecewise Quadratic Equation
3 views (last 30 days)
Show older comments
MarshallSc
on 3 Dec 2021
Answered: Walter Roberson
on 3 Dec 2021
How can I solve a second order quadraic nonlinear equation for each components of two matrices. For example, having:
a=rand(10,10); b=rand(10,10);
For the equation:
I'm looking for the analytical solution. I tried to write a code but I don't know what solver to use, ODE45 or dsolve.
Also, if I want to solve the gradient of this equation (getting the antiderivative of the equation to make it first order equation) which will be solmething like this:
How can I solve them? I'd appreciate it if someone can help me!
2 Comments
Walter Roberson
on 3 Dec 2021
Is that x double-prime, quantities individually squared, quantities then individually multiplied by themselves?
Is that x double-prime, quantities individually squared, matrix-multiply by itself (inner product)?
Is that x double-prime, matrix-multiply by itself (inner product) to do the part, then again matrix-multiplied by itself?
That is, I am not clear as to why you are not using ?
Accepted Answer
Walter Roberson
on 3 Dec 2021
syms a b x(t)
x__prime = diff(x)
x__prime__prime = diff(x__prime)
eqn = a/(x__prime__prime*x__prime__prime) == b
sol = dsolve(eqn)
syms x_2(t)
x_2__prime = diff(x_2)
x_2__prime__prime = diff(x_2__prime)
eqn_2 = a/(x__prime__prime * x_2__prime__prime) == b
sol_2 = dsolve(eqn_2)
I think for sol_2 there is a fundamental problem that you are asking to solve one equation with respect to two functions.
0 Comments
More Answers (0)
See Also
Categories
Find more on Ordinary Differential Equations in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!