General Solution for a Bernoulli Equation with Trigonometric Functions

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SUMMARY

The discussion focuses on solving a Bernoulli differential equation of the form y' + 4xy = 10xy²cos(x²). The user identifies key components of the equation, specifically a = 2, p(x) = 4x, and g(x) = 10xcos(x²). The change of variables is applied using u(x) = [y(x)]^(1-a) = y^(-1), leading to the transformed equation u' - 4xu = -10xcos(x²). The user expresses difficulty in solving the integral required for the general solution but ultimately resolves the issue independently.

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Homework Statement


Find the general solution of the following differential equation.
y'+4xy=10xy2cos(x2)

Homework Equations


The usual Bernoulli equation ones:
y'+p(x)y = g(x)ya
u(x)=[y(x)]1-a
u'+(1-a)pu = (1-a)g

The Attempt at a Solution


I got up until the general solution part.. I'll just type bits of it out because it'll take me ages (I'm a slow typer).

So in the equation, a=2, p(x)=4x, g(x)=10xcos(x2)

Change of variables:
u(x)=[y(x)]1-a = y-1

and u'+(1-a)pu = (1-a)g
=> u'-4xu = -10xcos(x2)

Now here's where I get confused..
General solution:
u= e[tex]\int[/tex]p(x)dx[[tex]\int[/tex]r(x)e[tex]\int[/tex]p(x)dxdx+c
where p=-4x, r=-10xcos(x2)

u= e[tex]\int[/tex]-2x^2[[tex]\int[/tex](-10xcos(x2)e[tex]\int[/tex]-2x^2)dx+c

Argh.. that's messy, I hope it makes sense.

Anyway, I can't seem to figure out that integral... I've used parts and stuff but I don't seem to be getting anywhere.

Any help would be appreciated.
 
Last edited:
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Nevermind, I figured it out.
 

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