Find using the defintion f '(c) lim = f(x) - f(c)
x -> c _______
x - c
the gradient function f ' (x) for:
a) f(x) = 1/x
b)f(x) = √ x
[My tutor told me to rationalize before doing the question for part b but how do i rationalize this]
Sorry I didn't realize that the definition for f '(c) was all over the place....sorry about that.
For Part b is the answer:
(x-c)/(x√x + x√c - c√x - c√c
and for Part (a) how am I supposed to find f '(x)
Sorry this question is really confusing me
coz there are so many x's and c's.......
That's it but if you try computing you'll see that this limit is an indeterminate form. (both the numerator and the denominator tend to 0) If you hadn't expanded the numerator, it would have given you
And isn't an indeterminate form any longer. Can you find the value of this limit ?
The gradient of taken at is as long as . Thus for .and for Part (a) how am I supposed to find f '(x)
Sorry this question is really confusing me
coz there are so many x's and c's.......