Cuse these difference quotients

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Cuse these difference quotients!

Homework Statement


http://www.webassign.net/www14/symImages/5/8/30f1e141e81c6a3333af41547f8ff2.gif

Evaluate the difference quotient for the given function

http://www.webassign.net/www14/symImages/4/6/bda668fa415dbf5d0c9c2ba4c031d2.gif

Homework Equations


n/a

The Attempt at a Solution


I seem to have the wrong mindset while doing these.

I got 0.

Actually, I don't really know exactly what I'm even going for here.
 
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My main thing is that I don't know what the outcome should look like.

It was during the last few weeks of my senior year of high school so I didnt exactly make it to class every day and I missed this stuff. Its coming back to bite me in college now.
 


I told you, just substitute the form for f(x) into the difference quotient and try and do some algebra to simplify it. What is f(5)? This isn't a big conceptual problem.
 


leftyguitarjo said:

Homework Statement


http://www.webassign.net/www14/symImages/5/8/30f1e141e81c6a3333af41547f8ff2.gif

Evaluate the difference quotient for the given function

http://www.webassign.net/www14/symImages/4/6/bda668fa415dbf5d0c9c2ba4c031d2.gif


Homework Equations


n/a


The Attempt at a Solution


I seem to have the wrong mindset while doing these.

I got 0.

Actually, I don't really know exactly what I'm even going for here.

Later on you will see that the slope of the tangent line at a point say P(a,f(a)), is given by:

[tex]\lim_{x\rightarrow a}\frac{f(x)-f(a)}{x-a}=f'(a)[/tex]

And only the quotient [tex]\frac{f(x)-f(a)}{x-a}[/tex] is the slope of secat line.

So, you are given a function f(x) and then asked to find the quotient.

[tex]\frac{f(x)-f(5)}{x-5}[/tex] so what u want to do is replace f(x) with what you are given, in other words, write the function f(x)=... whatever it equals, and then for f(5), you first want to evalulate f(5)=...whatever it equals. You evaluate f(5) by plugging 5 in

[tex]f(x)=\frac{x+7}{x+5}[/tex]
 
Last edited by a moderator:


leftyguitarjo said:
My main thing is that I don't know what the outcome should look like.

It was during the last few weeks of my senior year of high school so I didnt exactly make it to class every day and I missed this stuff. Its coming back to bite me in college now.

Dick said "Why don't you show us what you did? " Why will you not do that?