Hard Problem (for me): lim (Δx-->0) [7-8(1+Δx)]-1(-1)/Δx

[nbg273]

The limit represents f '(c) for a function f(x) and a number c. Find f(x) and c.

lim (Δx-->0) [7-8(1+Δx)]-1(-1)/Δx

So the story is... my teacher assigns this as a homework problem that's gonna turn up on our exam tomorrow, but without going over a single problem with a triangle thing in it. I looked it up and apparently it's a "change" symbol?
Please, I really just need the answer and steps written down so I can at least try to learn this before my next exam in about 12 hours. I'm willing to try to learn, and not just looking for the answer, but I have no time and honestly learn best by getting the answer and seeing the steps.

Any help would be great, thanks!

 

[stapel]

The limit represents f '(c) for a function f(x) and a number c. Find f(x) and c.

lim (Δx-->0) [7-8(1+Δx)]-1(-1)/Δx

So the story is... my teacher assigns this as a homework problem that's gonna turn up on our exam tomorrow, but without going over a single problem with a triangle thing in it. I looked it up and apparently it's a "change" symbol?
Please, I really just need the answer and steps written down so I can at least try to learn this before my next exam in about 12 hours. I'm willing to try to learn, and not just looking for the answer, but I have no time and honestly learn best by getting the answer and seeing the steps.

If your instructor is testing over material which has not been taught (and for which no reasonable time has been allowed even for self-study), then I would strongly suggest that you have a talk with somebody in administration, such as the chair of the department, or the dean of the college. Because this is not ethical conduct. :shock:

 

[nbg273]

If your instructor is testing over material which has not been taught (and for which no reasonable time has been allowed even for self-study), then I would strongly suggest that you have a talk with somebody in administration, such as the chair of the department, or the dean of the college. Because this is not ethical conduct. :shock:

As we were going home, he said for homework, read this page in your textbook, as there might be a problem on your exam about it next class... Is that still unethical conduct??? Also, I figured out c, but do you know how to get f(x)???