Integrating Factor Method Problem

bdh2991
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Homework Statement



Find the general solution of the given differential equation cosxy'+(sinx)y=1



The Attempt at a Solution



I divided everything by cosx and got : y'+(tanx)y=secx

then after doing e to the integral of tanx i got : ∫d/dx[secx*y]=∫secx

after integrating and simplifying i got y= ln|secx+tanx|/secx + Ccosx

the answer in the book is y= sinx + Ccosx

the weakest part of my math is simplifying (or algebra) what did i do wrong or what do i need to do?
 
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When you multiplied by the integrating factor, you forgot to do it to the righthand side of the equation.
 
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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