Rewriting Expression Homework: Tips & Hints for Solving

[Niles]

Homework Statement

Hi

I have an expression on the form

$$\frac{\tau }{{\alpha - \varepsilon + i\eta }}\left( {1 + \frac{\tau }{{\alpha - \varepsilon + i\eta }}G} \right)$$

where i denotes the complex i. I have to bring this into the form

$$\frac{\tau }{{\alpha - \varepsilon + f\left( \alpha \right)}}$$

where f is some function. I have been sitting with this for most of the morning. Can you give me a hint on how to get there? I have tried many ways of rewriting the expression, but still far from the above.

 

[tiny-tim]

Hi Niles!

I don't get it …

there's clearly a τ² in the expression, so how can it not be in the answer?

What is the context?

 

[Niles]

I have solved an equation, and I am asked to show that the result I get is equal to the last expression above. Perhaps I have made an error. I'll re-check.