Solve the following differential equation

fsujoseph
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Homework Statement



Solve the differential equation. -x2(dy/dx) + xy = x2y2 * sin(x)

Homework Equations


None.

The Attempt at a Solution


I first figured out that this was a Bernoulli's equation. I distributed the x2 to make it simpler. From there I divided everything by y2 to get y-2(dy/dx) + (x3/y) = x4sin(x)

From there I let w = 1/y dw=-1/y2 dy and then multiplied through by -1 so dw would fit in.

Now I have dw/dx - wx3 = -x4sin(x)

Then I let P(x) = x3 Mu(x) = eintegral(x^3)

This gave me Mu(x) = e1/4*x^4

My problem is that when you multiply that back into the equation and get to the point where you integrate, there is 3 terms on the right side (a triple integral is what you call it?). I am unsure of how to approach it, I must have done something wrong. The sin(x) is what is different from any Bernoulli's I have done. Thanks
 
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Oh wow never mind it was -x^2 not x^-2
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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