http://img337.imageshack.us/img337/7410/problem3b.jpg

I understand how they did everything except the last step, from 1/(-s/(s+1)^2) to -(s+1)^2/s

Could someone clarify? Thanks.

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- Oct 15th 2009, 03:55 PMEvan.KimiaEasy simplification of a function
http://img337.imageshack.us/img337/7410/problem3b.jpg

I understand how they did everything except the last step, from 1/(-s/(s+1)^2) to -(s+1)^2/s

Could someone clarify? Thanks. - Oct 15th 2009, 04:26 PMDefunkt
Well...

Using the fact that $\displaystyle \frac{1}{\frac{u}{v}} = 1 \cdot \frac{v}{u} \Rightarrow \frac{1}{\frac{s}{(s+1)^2}} = 1 \cdot \frac{(s+1)^2}{s}$

That is, dividing a term by x is like multiplying it by $\displaystyle \frac{1}{x}$. In this example, our x is $\displaystyle -\frac{s}{(s+1)^2}$ and so our 1/x is $\displaystyle -\frac{(s+1)^2}{s}$ - Oct 15th 2009, 04:27 PMskeeter
- Oct 15th 2009, 05:50 PMEvan.Kimia
Thats what i thought, i wanted to be certain. Thanks!