Determining if a function is differentiable at the indicated point

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Homework Help Overview

The discussion revolves around determining the differentiability of a piecewise function at a specific point, x=1. The function is defined as F(x) = x^2 + 1 for x < 1 and F(x) = 2x for x ≥ 1.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants explore the conditions for differentiability, specifically the need for left-sided and right-sided derivatives to be equal at the point of interest. Questions arise regarding the evaluation of these derivatives and the implications of piecewise definitions.

Discussion Status

Some participants have provided insights into the requirements for differentiability, while others are seeking clarification on how to compute derivatives from the piecewise function. There is an ongoing exploration of the concept without a definitive conclusion yet.

Contextual Notes

Participants are discussing the implications of having different functional definitions on either side of the point x=1, and the need for both derivatives to exist and be equal for differentiability to hold. There is also mention of evaluating derivatives at specific points, which may lead to further questions about constant functions.

dugga boy
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How do you determine this?

F(x) x^2 +1 if x<1
F(x) 2x if x >= 1 at x=1

Are there designated steps? I understand that it is the derivative, but I don't understand the differentiable at the indicated point part..
 
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For a function to be differentiable at a point, its left sided and right sided derivatives must be equal. Usually the function is the same on both sides of a point, but for this function it has two different pieces.
 
I don't understand how is it different on the left sided and right sided? Would you put 1 for the value of x and get a solution that way?
 
On the "left" of 1, the function is defined as F(x)=x^2 +1, then F'(1)=_____
On the "right" of 1, the function is defined as F(x)=2x, then F'(1)=_____

If these two values exist and are equal, then the function is differentiable at 1.
 
Ok so only if first there is a vale for f'(x) and if the two valeus match is the function "differentiable" at the indicated point...Awesome! THANK YOU
One more question if you would be so kind...how do you evaluate if F'(x) = an integer with no variable? F'(1) = 2 since F(x) =2x
 
If there's no variable then the function doesnt...vary. ie no matter what x is, the function is just constant.
 

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