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Consider the function ()=∣−∣+ Prove that this function is not differentiable at =1 using the limit definition of the derivative. What is the result of the following limit?

User Fra
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Final answer:

To prove that the function f(x) = |x-1| is not differentiable at x = 1 using the limit definition of the derivative, we need to show that the left-hand limit and the right-hand limit of the difference quotient do not equal each other. By finding the left-hand limit and the right-hand limit and showing that they are not equal, we can conclude that the function is not differentiable at x = 1.

Step-by-step explanation:

To prove that the function f(x) = |x-1| is not differentiable at x = 1 using the limit definition of the derivative, we need to show that the left-hand limit and the right-hand limit of the difference quotient do not equal each other.

Step 1:

Start by finding the left-hand limit:

limh→0-[f(1+h) - f(1)] / h

Substitute the function f(x):

limh→0-[|1+h-1| - |1-1|] / h

Simplify:

limh→0-[|h|] / h

As h approaches 0 from the left, |h| / h approaches -1.

Step 2:

Next, find the right-hand limit:

limh→0+[f(1+h) - f(1)] / h

Substitute the function f(x):

limh→0+[|1+h-1| - |1-1|] / h

Simplify:

limh→0+[|h|] / h

As h approaches 0 from the right, |h| / h approaches 1.

Step 3:

Since the left-hand limit (-1) does not equal the right-hand limit (1), the function is not differentiable at x = 1.

User Gbvb
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