Simple differential quesion

In summary, the equation is y'+2y = 4t^2 with initial condition y(1) = 2. The solution is y=t^2 + t^(-2) and t>0, as both t's being raised to the power of two cancels any negative values. Additionally, t is typically restricted to be greater than or equal to 0 for modelling purposes.
  • #1
jwqwerty
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0

Homework Statement



1. ty'+2y = 4t^2 , y(1) = 2

Homework Equations


The Attempt at a Solution



1. I know how to get the answer but i have a trivial question. The answer is y=t^2 + t^(-2) and t>0. I do not get why t>0. Why can't t be R except 0?
 
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  • #2
I think it can be all the reals except zero, but the fact that both t's are to the power of two cancels any negatives.
So you would really just end up with all the positive reals as any negatives would produce the same solution as positives.
 
  • #3
Agree with Daniiel, you can also consider it from the physical standpoint, that generally t represents time and for modelling purposes we typically restrict [itex]t \geq 0[/itex] to correspond with this notion.
 

1. What is a simple differential equation?

A simple differential equation is an equation that contains one or more derivatives of a function. It relates the rate of change of a variable to the value of the variable itself.

2. What is the purpose of solving a simple differential equation?

The purpose of solving a simple differential equation is to find a function that satisfies the equation and helps us understand the behavior or relationships between variables in a system.

3. What are the different methods for solving a simple differential equation?

There are several methods for solving a simple differential equation, including separation of variables, integrating factors, and using power series or Laplace transforms.

4. How do you determine the order of a simple differential equation?

The order of a simple differential equation is determined by the highest derivative present in the equation. For example, a first-order differential equation has a first derivative, while a second-order differential equation has a second derivative.

5. What are some real-world applications of simple differential equations?

Simple differential equations are used in many fields, including physics, engineering, economics, and biology, to model and understand natural phenomena such as population growth, radioactive decay, heat transfer, and chemical reactions.

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