So that it's easier to read, the DE is

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I'll have a go of it now...

Edit: I'm going to assume that you've made a typo, because if it involves it is near impossible to get it to the required form

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So I'll fix the typo so that it should say instead. Then it is easy to get to the required form

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So, the original DE should be (I think...)

Some rearranging will give you

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Here so .

So make the substitution

Now find . Notice that .

So .

So, when substituting everything into the DE, it becomes

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This is first order linear, so can be solved using an integrating factor.

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Phew...