Limit Problem, See comments for equation:
Use the limit definition to find the slope of the function: \[f(x)= 2/(x-1)\]
\[f'(x)=\lim_{h \rightarrow 0}\frac{f(x+h)-f(x)}{h}=\lim_{h \rightarrow 0}\frac{\frac{2}{x+h-1}-\frac{2}{x-1}}{h}\]
did you get this for the first step?
\[=\lim_{h \rightarrow 0}\frac{\frac{2(x-1)}{(x+h-1)(x-1)}-\frac{2(x+h-1)}{(x-1)(x+h-1)}}{h}=\lim_{h \rightarrow 0}\frac{\frac{2(x-1)-2(x+h-1)}{(x+h-1)(x-1)}}{h}\]
\[=\lim_{h \rightarrow 0}\frac{\frac{2x-2-2x-2h+2}{(x+h-1)(x-1)}}{h} \cdot \frac{\frac{1}{h}}{\frac{1}{h}}\]
\[\lim_{h \rightarrow 0}\frac{-2h}{(x+h-1)(x-1)} \cdot \frac{1}{h}\]
\[\lim_{h \rightarrow 0}\frac{-2}{(x+h-1)(x-1)}=\frac{-2}{(x+0-1)(x-1)}=\frac{-2}{(x-1)(x-1)}=\frac{-2}{(x-1)^2}\]
Alright. Not the way I went with it, what so ever. I'm going to have to spend some time understanding your steps. Again, myininaya, you've helped me out, thank you very much!
I have another way in my mind i can put that down if you like
\[\lim_{h \rightarrow 0}\frac{\frac{2}{x+h-1}-\frac{2}{x-1}}{h} \cdot \frac{(x+h-1)(x-1)}{(x+h-1)(x-1)}\] \[\lim_{h \rightarrow 0}\frac{2(x-1)-2(x+h-1)}{h(x+h-1)(x-1)}\]
\[\lim_{h \rightarrow 0}\frac{2x-2-2x-2h+2}{h(x+h-1)(x-1)}\]
\[\lim_{h \rightarrow 0}\frac{-2h}{h(x+h-1)(x-1)}=\lim_{h \rightarrow 0}\frac{-2}{(x+h-1)(x-1)}\]
and i did this part above
instead of combining the fractions like I did in the first way, I could have first just multiply by the factors of numerator's denominator like i did in the 2nd way
denominators*
Again, thank you for shedding some light on this. My algebra is a little rusty, and these problems really exploit it. I will have to go back and work on that.
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