Solving the Differential Equation

Manni
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I'm given the differential dy/dx = x*y*sinx / (y+1) and I need to find its solution.

I apply the following steps,

(y+1)/y*dy = x*sinx*dx

1 + 1/y*dy = x*sinx*dx

∫ 1 + 1/y*dy = ∫ x*sinx*dx

...skipping a few steps for convenience I get the equation

y + lny = -x*cosx + sinx

My problem now is that I don't know how do I solve for y.
 
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Manni said:
I'm given the differential dy/dx = x*y*sinx / (y+1) and I need to find its solution.

I apply the following steps,

(y+1)/y*dy = x*sinx*dx

1 + 1/y*dy = x*sinx*dx

∫ 1 + 1/y*dy = ∫ x*sinx*dx

...skipping a few steps for convenience I get the equation

y + lny = -x*cosx + sinx

My problem now is that I don't know how do I solve for y.

You can't solve nicely for y. That's often the case. But you've gotten rid of the derivatives, that should be enough. I do miss seeing an arbitrary constant (a '+C') somewhere in your solution.
 
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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