# I need help with this question

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#1
I need help with this question. The picture is shown below.
0
1 month ago
#2
hmm, i'm not 100% sure but my first thought was, for some h in the reals, we can get an expression for f'(c-h) from the definition. then consider f'(c)+f'(c-h), which should come out to the limit in the show that. if either limit exists in isolation then their sum should also exist. not too sure (yet?) about the second part though, sorry
Last edited by ish101; 1 month ago
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1 month ago
#3
ooh, this is quite shaky logic but at the least it may trigger some ideas. if said limit=f'(c)+f'(c-h), then as h tends to 0, f'(c-h) tends to f'(c) ==> limit tends to 2f'(c)
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1 month ago
#4
Attachment 879908
Anyone got any clue?
Saying f is differentiable at c means the limit exists for both positive and negative h. So consider the two sequences where x -> c from both above and below and combine.
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1 month ago
#5
I don't think you should be posting University of Central Lancashire assignment questions on here....
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1 month ago
#6
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1 month ago
#7
I need help with this question. The picture is shown below.
If you need help to do a simple derivative definition-type for an assignment, then unfortunately your problems are probably more fundamental than simply completing this assignment.

Edit: 4 months ago you were asking questions which involved odes/wronskians etc. Something just ain't right.
Last edited by mqb2766; 1 month ago
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