Solving a Differential Equation: Need Help!

In summary, a differential equation is a mathematical equation that relates a function with its derivatives and is used to model dynamic systems in various fields. They are important because they allow us to understand and predict the behavior of complex systems and are solved by finding a function that satisfies the equation. There are different types of differential equations, including ordinary, partial, and stochastic, and not all equations have an explicit solution, requiring the use of numerical methods or having no solution at all.
  • #1
tandoorichicken
245
0
I'm having a little trouble with this differential equation. Usually I have no problem separating out the y's and the t's but this one is different:

ty' - y = t^3 - 2t on (0, [itex]\infty[/itex])

A little hep please?
 
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  • #2
Since [itex] t\neq 0 [/itex],u can, perform a division and obtain

[tex]\frac{dy}{dt}-\frac{y}{t}=t^{2}-2 [/tex]

Solve this nonhomogenous linear first order ODE,knowing that the homogenous equation is separable...


Daniel.
 
  • #3


Sure, I would be happy to provide some assistance with this differential equation. First, let's rewrite the equation in a more standard form:

y' - (1/t)y = t^2 - 2

To solve this equation, we can use the method of integrating factors. The integrating factor is defined as e^(∫(1/t)dt), which in this case is e^(ln|t|) = t. Multiplying both sides of the equation by t, we get:

ty' - y = t^3 - 2t

ty' - (ty) = t^4 - 2t^2

Applying the product rule on the left side, we get:

t(y' - y) = t^4 - 2t^2

Integrating both sides with respect to t, we get:

∫t(y' - y)dt = ∫(t^4 - 2t^2)dt

Using integration by parts on the left side, we get:

ty - ∫ydt = ∫(t^4 - 2t^2)dt

Simplifying, we get:

ty - y = t^5/5 - 2t^3/3 + C

Finally, solving for y, we get the general solution:

y = (t^5/5 - 2t^3/3 + C)/t

To find the particular solution, we need to use the initial condition of y(0) = 0. Plugging in t = 0 and y = 0 into the general solution, we get C = 0. Therefore, the particular solution to this differential equation is:

y = (t^5/5 - 2t^3/3)/t = t^4/5 - 2t^2/3

I hope this helps! Let me know if you have any further questions.
 

Related to Solving a Differential Equation: Need Help!

1. What is a differential equation?

A differential equation is a mathematical equation that relates a function with its derivatives. It describes the relationship between a function and its rate of change, and is often used to model dynamic systems in various fields, such as physics, engineering, and economics.

2. Why are differential equations important?

Differential equations are important because they allow us to understand and predict the behavior of complex systems. They are used in various fields to model real-world phenomena and make predictions about their future behavior. They also provide a powerful tool for solving a wide range of problems in science and engineering.

3. How do you solve a differential equation?

The process of solving a differential equation involves finding a function that satisfies the equation. This can be done through various methods, such as separation of variables, substitution, or using specific techniques for different types of equations. Some equations may also require numerical methods to find an approximate solution.

4. What are the different types of differential equations?

There are several types of differential equations, including ordinary differential equations, partial differential equations, and stochastic differential equations. Ordinary differential equations involve a single independent variable, while partial differential equations involve multiple independent variables. Stochastic differential equations involve random variables and are commonly used in modeling systems with uncertain or random behavior.

5. Why do some differential equations have no explicit solution?

Not all differential equations can be solved analytically, meaning that a closed-form solution cannot be found. This is often the case for non-linear equations or equations with complex terms. In these cases, numerical methods can be used to find approximate solutions. It is also possible that a differential equation has no solution at all.

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