# Does f ' (0) Exists?

Discussion in 'Calculus' started by nycmathguy, Jun 5, 2022.

1. ### nycmathguy

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Calculus
Section 2.7

Can you do 57? I will then do 58 using your reply as a guide.

nycmathguy, Jun 5, 2022

2. ### MathLover1

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57.
given:

f'(a)=

a=0

f'(0)=

f'(0)=lim(h*sin(1/h))/h as h->0

f'(0)=lim(sin(1/h)) as h->0

f'(0)=lim(sin(1/0)) -> function oscillating no matter how far we go

so, limit f'(0) DNE

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MathLover1, Jun 6, 2022
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3. ### nycmathguy

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What do you mean by h tends to a box or square?

nycmathguy, Jun 6, 2022
4. ### MathLover1

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where do you see that "h tends to a box or square"?
ah, I see now on the image above
I was using wolfram alpha and didn't noticed it made a square instead of a

I said h->a

Last edited: Jun 6, 2022
MathLover1, Jun 6, 2022
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