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# differentiating a piecewise function watch

1. http://imgur.com/ep7XFNJ

Thoughts?
2. (Original post by Mihael_Keehl)
http://imgur.com/ep7XFNJ

Thoughts?
Quite a few, you got any yourself? Seems a bit weird that you're using as a continuous variable, by the way.
3. (Original post by Mihael_Keehl)
http://imgur.com/ep7XFNJ

Thoughts?
What makes you think the function is both left and right differentiable, by the way?
4. (Original post by Mihael_Keehl)
http://imgur.com/ep7XFNJ

Thoughts?
I am not known for my pure maths but for differentiation continuity is a prerequisite
5. (Original post by Mihael_Keehl)
http://imgur.com/ep7XFNJ

Thoughts?
vomit; ignore.
6. (Original post by Mihael_Keehl)
http://imgur.com/ep7XFNJ

Thoughts?
(Original post by Zacken)
What makes you think the function is both left and right differentiable, by the way?
(Original post by TeeEm)
I am not known for my pure maths but for differentiation continuity is a prerequisite
My second year analysis springs to mind (as that's checking whether the function is able to be differentiated from both the right and left and side)
7. (Original post by TeeEm)
I am not known for my pure maths but for differentiation continuity is a prerequisite
lol!

Just ignore the second function, it's a load of crap anyway.
8. (Original post by Slowbro93)
My second year analysis springs to mind (as that's checking whether the function is able to be differentiated from both the right and left and side)
Surely this is basic a-level / advanced GCSE?
9. (Original post by Bath_Student)
Simply differentiate n^2 + 1 and plug n=1 into the answer.

Should be approximately equal to two.
Remember what it was you said yesterday? Not to say anything when you're clueless? Yeah, that applies here.
10. (Original post by Zacken)
Quite a few, you got any yourself? Seems a bit weird that you're using as a continuous variable, by the way.
I am not sure it is even possible.

(Original post by Zacken)
What makes you think the function is both left and right differentiable, by the way?
Draw the graph, there is a gap in there and so you cant draw a tanget to it or at least dx=0 so f'(1) doesnt exist.
11. (Original post by Slowbro93)
My second year analysis springs to mind (as that's checking whether the function is able to be differentiated from both the right and left and side)
Awesome, thanks for confirming that, saved me a quick wiki lookup.
12. (Original post by Bath_Student)
lol!

Just ignore the second function, it's a load of crap anyway.
13. (Original post by Mihael_Keehl)
I am not sure it is even possible.

Draw the graph, there is a gap in there and so you cant draw a tanget to it or at least dx=0 so f'(1) doesnt exist.
That's correct, your justification isn't the best, but I suppose it'll do at your level.
14. (Original post by Bath_Student)
Surely this is basic a-level / advanced GCSE?
It should be, but given that it's on the point I can't exactly remember the rule of just forgetting the second function (this is what a maths degree did to me )
15. (Original post by TeeEm)
I am not known for my pure maths but for differentiation continuity is a prerequisite
the dy/dx is e/z what I get is a gap in the graph for f'(x) so not possible right :P
(Original post by Bath_Student)
Simply differentiate n^2 + 1 and plug n=1 into the answer.

Should be approximately equal to two.
maybe in c1
I dont think it is that simple idk

(Original post by Slowbro93)
My second year analysis springs to mind (as that's checking whether the function is able to be differentiated from both the right and left and side)
16. (Original post by Slowbro93)
It should be, but given that it's on the point I can't exactly remember the rule of just forgetting the second function (this is what a maths degree did to me )
I have seen what it did to TeeEm, I have been warned not to study maths already

#engineeringmasterrace.
17. (Original post by Zacken)
That's correct, your justification isn't the best, but I suppose it'll do at your level.
Could I say that it is infinty?
18. (Original post by Slowbro93)
It should be, but given that it's on the point I can't exactly remember the rule of just forgetting the second function (this is what a maths degree did to me )
No, you're quite correct.

(Original post by Mihael_Keehl)
Could I say that it is infinty?
No. You say it is non-existent.
19. (Original post by Mihael_Keehl)
Could I say that it is infinty?
Nah, it just does not exist.

Sorry for my lousy faux-pas. I'll point at the time for my excuse..
20. (Original post by Zacken)
No, you're quite correct.

No. You say it is non-existent.
(Original post by Bath_Student)
Nah, it just does not exist.

Sorry for my lousy faux-pas. I'll point at the time for my excuse..

thnx guys

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