First-order differential equation

Mathematicsss

Homework Statement


y'+tanxy=sinx

Homework Equations



integrating factor I(x)= exp{lnIsecxI}[/B]

The Attempt at a Solution


I have secxy= integral of sinx I(x)
I am not sure how to integrate that because secx is in absolute value form.[/B]
 
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Mathematicsss said:

Homework Statement


y'+tanxy=sinx

Homework Equations



integrating factor I(x)= exp{lnIsecxI}[/B]

The Attempt at a Solution


I have secxy= integral of sinx I(x)
I am not sure how to integrate that because secx is in absolute value form.[/B]

There are two cases: (1) the values of ##x## make ##\sec(x) > 0##; or (2) the values of ##x## make ##\sec(x) < 0##. Just analyze both cases, although you need to worry about whether the solution ##y(x)## can remain meaningful if ##x## crosses from one region to the other.
 
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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