why do i receive error when do 'Implicit' solution true?
2 views (last 30 days)
Show older comments
syms y(x)
eqn=diff(y,x)==3*(x*y)^(1/2);
dsolve(eqn,'Implicit',true)
when i run this code
ans =
y(x) == 0
(y(x)^(3/2)*(C1 + 27*y(x)^(1/2)))^(2/3)/y(x) == (9*x)/((3^(1/2)*1i)/2 + 1/2)^2
(y(x)^(3/2)*(C1 + 27*y(x)^(1/2)))^(2/3)/y(x) == (9*x)/((3^(1/2)*1i)/2 - 1/2)^2
(y(x)^(3/2)*(C1 + 27*y(x)^(1/2)))^(2/3)/y(x) == 9*x
programme prints on the screen this but implicit solution of this diferential equation is x^(3/2)-sqrt(y)=C
if someone can help me it would be great, thanks!!!
0 Comments
Accepted Answer
Walter Roberson
on 27 Apr 2023
sol = dsolve(eqn, 'implicit', true)
arrayfun(@(X)isolate(X, y), sol)
You will see that they are different ways of writing it. There might potentially be theoretic differences if x or y(x) are negative or complex valued
2 Comments
Walter Roberson
on 2 May 2023
syms y(x)
eqn=diff(y,x)==3*(x*y)^(1/2);
sol = dsolve(eqn, 'implicit', true)
sol1 = arrayfun(@(X)isolate(X, y), sol);
arrayfun(@(X) sqrt(lhs(X)) == simplify(sqrt(rhs(X)), 'ignoreanalytic', true), sol1)
Notice that analytic constraints had to be ignored. You would have to prove that your version is valid for negative x.
More Answers (0)
See Also
Categories
Find more on Event Functions 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!