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Use the definition on continuity to determine all values of constant k for which f(x) is continuous at x = -2.

a) k = 2
b) k = -2
c) k = 0
d) k = 1

User Smokie
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Final answer:

To determine the values of constant k for which f(x) is continuous at x = -2, we need to use the definition of continuity and evaluate the limit of f(x) as x approaches -2 for each value of k given. The only value of k for which the function f(x) is continuous at x = -2 is k = 0.

Step-by-step explanation:

To determine the values of constant k for which f(x) is continuous at x = -2, we need to use the definition of continuity. A function f(x) is continuous at a point x = c if three conditions are met: 1) f(c) is defined, 2) the limit of f(x) as x approaches c exists, and 3) the limit and the value of f(x) at x = c are equal.

In this case, the function is continuous at x = -2 if and only if the limit of f(x) as x approaches -2 exists and is equal to f(-2). So, we need to evaluate the limit of f(x) as x approaches -2 for each value of k given.

a) For k = 2:

lim(x -> -2) f(x) = lim(x -> -2) (2x + 3) = 2(-2) + 3 = -1

Since the limit does not equal f(-2), the function is not continuous at x = -2.

b) For k = -2:

lim(x -> -2) f(x) = lim(x -> -2) (-2x + 3) = -2(-2) + 3 = 7

Since the limit does not equal f(-2), the function is not continuous at x = -2.

c) For k = 0:

lim(x -> -2) f(x) = lim(x -> -2) (0x + 3) = 3

Since the limit equals f(-2), the function is continuous at x = -2 for k = 0.

d) For k = 1:

lim(x -> -2) f(x) = lim(x -> -2) (x + 3) = -2 + 3 = 1

Since the limit does not equal f(-2), the function is not continuous at x = -2.

Therefore, the only value of k for which the function f(x) is continuous at x = -2 is k = 0.

User Yasser Mohsen
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