Question regarding Bernoulli Differential Equation

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Homework Help Overview

The discussion revolves around the classification of differential equations, specifically the Bernoulli Differential Equation and its relation to first order linear differential equations. Participants are examining the conditions under which a differential equation can be categorized as Bernoulli, particularly focusing on the case when n equals 1.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants explore the definition of Bernoulli Differential Equations and question how the equation transforms when n equals 1. There are attempts to rewrite the equations in standard forms and clarify the implications of these transformations.

Discussion Status

The discussion is ongoing, with some participants providing insights into the nature of first order linear differential equations and how they relate to the original question. There is a recognition of differing interpretations, particularly regarding the classification of the equation when n equals 1.

Contextual Notes

Some participants express difficulty in understanding the explanations provided, indicating a need for further clarification on the proofs and definitions discussed. The original poster is seeking to reconcile the definitions presented in a video with their understanding of the equations.

mathnoobie
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In a video I was watching regarding how to solve these, the lecturer said that
the form of a Bernoulli Differential Equation is y'+P(x)y=q(x)y^n
where n>1

This means that if n = 1, it wouldn't be a Bernoulli differential equation and would be a first order linear differential equation, but if n=1, y'+P(x)y=q(x)y doesn't take the form of y'+P(x)y=q(x), so how is this a first order linear differential equation?

, here is the video in case anyone wants to check it out.
 
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y'+P(x)y=q(x)y
y' + (P-q)y = 0

so P is P-q, and q is 0.
 
qbert said:
y'+P(x)y=q(x)y
y' + (P-q)y = 0

so P is P-q, and q is 0.

I don't quite understand what you did, if n=1

y'(y^-1)+P(x)-q(x)=0
 
standard form for a linear first order ode
y' + f(x) y = g(x)

a n=1 example of a Bernoulli like eqn
is y' + P(x) y = q(x) y
rewrite it as y' + (P(x) - q(x))y = 0.
this is in standard form with f(x) = P(x)-q(x) and g(x) = 0.
 
qbert said:
standard form for a linear first order ode
y' + f(x) y = g(x)

a n=1 example of a Bernoulli like eqn
is y' + P(x) y = q(x) y
rewrite it as y' + (P(x) - q(x))y = 0.
this is in standard form with f(x) = P(x)-q(x) and g(x) = 0.

Ah, but my original question was whether this was a Bernoulli equation or a First Order Linear DFQ(if it is, why), b/c in the video, they stated n=1 as a First Order LinDFQ
 
mathnoobie said:
Ah, but my original question was whether this was a Bernoulli equation or a First Order Linear DFQ(if it is, why), b/c in the video, they stated n=1 as a First Order LinDFQ

Do you not understand that the above posts are explaining to you that it is a first order linear DE and why?
 
LCKurtz said:
Do you not understand that the above posts are explaining to you that it is a first order linear DE and why?

Sorry, I don't. I'm not fluent enough to understand his proof without further explanation.

edit:AH, I think I finally understand the proof.

This means that the integrating factor would be e^(∫(fx)dx) correct?
 
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