2.1.7 DE y'e -2ty =2te^(-t^2)

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Discussion Overview

The discussion revolves around finding the general solution of the differential equation $\displaystyle y' - 2ty = 2te^{-t^2}$. Participants explore the steps involved in solving the equation, including the use of an integrating factor and integration techniques.

Discussion Character

  • Mathematical reasoning, Homework-related

Main Points Raised

  • Participants present a method for solving the differential equation, including the calculation of the integrating factor $u(t) = e^{-t^2}$.
  • There is a step-by-step breakdown of the solution process, including multiplying through by the integrating factor and simplifying the resulting expression.
  • Integration of the expression leads to a general solution, which is presented as $y = c_1 e^{t^2} - \frac{e^{-t^2}}{2}$.
  • Some participants note potential typos in the presented solutions.
  • One participant asks for clarification on where the two results presented differ, indicating a focus on the correctness of the solution steps.
  • Another participant points out that the order of terms does not affect the outcome, suggesting a possible misunderstanding regarding the presentation of the solution.

Areas of Agreement / Disagreement

There is no consensus on the presence of differences between the two results presented, as participants seem to focus on the order of terms rather than substantive differences in the solutions.

Contextual Notes

Participants express uncertainty regarding the accuracy of the solutions and mention possible typos, but do not specify what those typos are or how they affect the solutions.

karush
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Find the general solution of the given differential equation
$\displaystyle y^\prime -2ty =2te^{-t^2}\\$
Obtain $u(t)$
$\displaystyle u(t)=\exp\int -2t \, dt =e^{-t^2}$$%e^(-t^2)\\$
Multiply thru with $e^{-t^2}$
$(e^{-t^2})y^\prime -(e^{-t^2})2ty =(e^{-t^2})2te^{-t^2}\\$
Simplify:
$((e^{-t^2})y)'= 2te^{-2t^2}\\$
Integrate:
$\displaystyle e^{-t^2}y=\int 2te^{-2t^2} dt =-\frac{ e^{-2t^2}}{2}+c_1\\$
Divide by $e^{-t^2}$
$\displaystyle y=-\frac{e^{-t^2}}{2}+c_1 e^{t^2}\\$
Answer from $\textbf{W|A}$
$\displaystyle y=\color{red}{c_1 e^{t^2}-\frac{e^{-t^2}}{2}}$

ok got to be some typos in this
otherwise suggestions:eek:$$\tiny\textsf{Text Book: Elementary Differential Equations and Boundary Value Problems}$$
 
Last edited:
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karush said:
Find the general solution of the given differential equation
$\displaystyle y^\prime -2ty =2te^{-t^2}\\$
Obtain $u(t)$
$\displaystyle u(t)=\exp\int -2t \, dt =e^{-t^2}$$%e^(-t^2)\\$
Multiply thru with $e^{-t^2}$
$(e^{-t^2})y^\prime -(e^{-t^2})2ty =(e^{-t^2})2te^{-t^2}\\$
Simplify:
$((e^{-t^2})y)'= 2te^{-2t^2}\\$
Integrate:
$\displaystyle e^{-t^2}y=\int 2te^{-2t^2} dt =-\frac{ e^{-2t^2}}{2}+c_1\\$
Divide by $e^{-t^2}$
$\displaystyle y=-\frac{e^{-t^2}}{2}+c_1 e^{t^2}\\$
Answer from $\textbf{W|A}$
$\displaystyle y=\color{red}{c_1 e^{t^2}-\frac{e^{-t^2}}{2}}$

ok got to be some typos in this
otherwise suggestions:eek:$$\tiny\textsf{Text Book: Elementary Differential Equations and Boundary Value Problems}$$

Where do you believe those two results are different?
 
order of terms
 
karush said:
order of terms

Which is nothing. Addition is commutative.
 

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