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At x = 2, the function the piecewise function 2 times x plus 2 for x is less than or equal to 2 and 2 times x to the second power minus 2 for x is greater than 2 is considered which of the following?

At x = 2, the function the piecewise function 2 times x plus 2 for x is less than-example-1

2 Answers

4 votes

Step-by-step explanation:

A, Do it was the first time what

User Shubendrak
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8.3k points
3 votes

The correct answer is option A. Both continuous and differentiable.

To determine the continuity and differentiability of the given piecewise function
\( f(x) \), we need to check the conditions at the point
\( x = 2 \) where the function changes its definition.

For continuity:

A function is continuous at a point
\( x = a \) if the following three conditions are met:

1.
\( f(a) \) is defined.

2. The limit of
\( f(x) \) as
\( x \) approaches
\( a \) from the left
(\( \lim_{{x \to a^-}} f(x) \)) exists.

3. The limit of
\( f(x) \) as
\( x \) approaches
\( a \) from the right
(\( \lim_{{x \to a^+}} f(x) \)) exists.

4.
\( \lim_{{x \to a^-}} f(x) = \lim_{{x \to a^+}} f(x) = f(a) \)

For differentiability:

A function is differentiable at a point
\( x = a \) if the following condition is met:

1. The derivative
\( f'(a) \) exists.

Now let's analyze the given function at \( x = 2 \):

1. For continuity:

-
\( f(2) = 2(2) + 2 = 6 \)

-
\( \lim_{{x \to 2^-}} f(x) = \lim_{{x \to 2^-}} (2x + 2) = 6 \)

-
\( \lim_{{x \to 2^+}} f(x) = \lim_{{x \to 2^+}} (2x^2 - 2) = 6 \)

- The above limits and
\( f(2) \) are equal, so the function is continuous at
\( x = 2 \).

2. For differentiability:

- The derivative
\( f'(x) \) exists for both
\( 2x + 2 \) and
\( 2x^2 - 2 \) at
\( x = 2 \), so the function is differentiable at
\( x = 2 \).

Therefore, the correct answer is A. Both continuous and differentiable.

User Greg Petr
by
8.2k points