Second Order Linear Diff Eq

In summary, a second order linear differential equation is a mathematical equation that relates a function to its first and second derivatives. It can be solved by identifying the type and method of solution, using techniques such as separation of variables or Laplace transforms, and applying initial conditions. These equations have various applications in science, including in physics, engineering, and economics, and can have multiple solutions due to the presence of arbitrary constants and the nature of the given function.
  • #1
KleZMeR
127
1
Quadratic Polynomial can't satisfy second order linear differential equation with constant coefficients... WHY?
and
if possible, how would I show this? Does it have to do with independence?
 
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  • #2
ok

well i figured it out if anone cares
 
  • #3


The reason why a quadratic polynomial cannot satisfy a second order linear differential equation with constant coefficients is because such equations require the highest order term to have a coefficient that is not equal to zero. In a quadratic polynomial, the highest order term is the term with the squared variable, and it always has a coefficient of one. This means that no matter what constant coefficients are used in the equation, the highest order term will always have a coefficient of one, which does not satisfy the requirement for a second order linear differential equation.

To show this, we can consider a general form of a second order linear differential equation with constant coefficients:

ay'' + by' + cy = 0

If we substitute a quadratic polynomial, such as x^2, for y, we get:

a(2) + b(2x) + c(x^2) = 0

Simplifying, we get:

2a + 2bx + cx^2 = 0

Since the highest order term is cx^2, we can see that the coefficient of this term will always be equal to c, which is not dependent on the constant coefficients a and b. This means that no matter what values we choose for a and b, the coefficient of the highest order term will always be equal to one, which does not satisfy the requirement for a second order linear differential equation.

Therefore, it is not possible for a quadratic polynomial to satisfy a second order linear differential equation with constant coefficients. This is not related to independence, but rather the specific requirements for the form of a second order linear differential equation.
 

Related to Second Order Linear Diff Eq

1. What is a second order linear differential equation?

A second order linear differential equation is a mathematical equation that describes the relationship between a function, its first derivative, and its second derivative. It can be written in the form of:
y'' + p(x)y' + q(x)y = r(x), where p(x) and q(x) are continuous functions and r(x) is a given function.

2. What is the difference between a first order and a second order linear differential equation?

The main difference between a first and second order linear differential equation is the number of derivatives present in the equation. A first order equation only has one derivative, while a second order equation has two. This means that a second order equation is more complex and requires more information to solve.

3. How do you solve a second order linear differential equation?

To solve a second order linear differential equation, you need to follow a specific process. First, you need to identify the type of equation (homogeneous or non-homogeneous) and the method of solution (undetermined coefficients or variation of parameters). Then, you can use techniques such as separation of variables, integrating factors, or Laplace transforms to find the general solution. Finally, you can use initial conditions to find the particular solution.

4. What are the applications of second order linear differential equations in science?

Second order linear differential equations have various applications in science, such as in physics, engineering, and economics. They can be used to model and predict the behavior of systems that involve acceleration, oscillation, or growth/decay. For example, in physics, they are used to describe the motion of a mass on a spring or the behavior of a circuit with an inductor and capacitor.

5. Can a second order linear differential equation have multiple solutions?

Yes, a second order linear differential equation can have multiple solutions. This is because the general solution of a second order equation contains two arbitrary constants, which can take on different values. Additionally, if the equation is non-homogeneous, it can have an infinite number of particular solutions, depending on the given function r(x).

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