Efficiently Solve a Non-Linear ODE with Trigonometric Functions [SOLVED]

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In summary, the problem is a non-linear ODE that appears to be exact, but after taking the partial derivatives, it is found to be non-exact. However, the mistake was due to not writing it in differential form and the solution is found by integrating both sides with respect to x.
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Help solving this ODE [SOLVED]

Homework Statement



[itex]\frac{dy}{dx} = \frac{e^{-x}cosy - e^{2y}cosx}{-e^{-x}siny+2e^{2y}sinx}[/itex]

Homework Equations





The Attempt at a Solution



First, this is non-linear, not a bernoulli, non-separable, and looks hopeful for an exact. But when I take the partials I get the derivatives as being negatives of one-another.
EDIT
Nevermind, I found out what I was doing wrong. I was being lazy and didn't actually write it in differential form, keeping the negative sign when taking the appropriate partials and ended up with the two results being negatives of each other.
 
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The solution isM = -e^(-x)cosy + e^(2y)cosx N = e^(-x)siny - 2e^(2y)sinx Integrating both sides with respect to x: \int M dx = \int N dy -e^(-x)siny + e^(2y)sin(x) = c where c is the constant of integration.
 

FAQ: Efficiently Solve a Non-Linear ODE with Trigonometric Functions [SOLVED]

How do I identify if a differential equation is non-linear?

To identify if a differential equation is non-linear, you will need to look at the highest power of the dependent variable and its derivatives. If the highest power is greater than 1, then the equation is non-linear.

What is the general approach for solving a non-linear ODE with trigonometric functions?

The general approach for solving a non-linear ODE with trigonometric functions involves using substitution and integration techniques. First, you will need to identify a trigonometric function that can be used as a substitution for the dependent variable. Then, you will need to integrate both sides of the equation to solve for the unknown function.

Can I use trigonometric identities to simplify the equation before solving it?

Yes, you can use trigonometric identities to simplify the equation before solving it. This can make the integration process easier and help you arrive at the solution more efficiently.

Is there a specific method for solving non-linear ODEs with trigonometric functions?

There is no one specific method for solving non-linear ODEs with trigonometric functions. It ultimately depends on the specific equation and the techniques that work best for it. Some common methods include the substitution method, the power series method, and the Laplace transform method.

How do I check if my solution to a non-linear ODE with trigonometric functions is correct?

You can check if your solution is correct by substituting it back into the original equation and seeing if it satisfies the equation. You can also use a graphing calculator to graph both the original equation and your solution and see if they match up.

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