Check the points where the constant function f(x)=kf(x)=k is continuous.

Answer: The constant function f(x)=kf(x)=k is continuous at all points x∈Rx \in \mathbb{R}.

Step-by-step solution

Step 1: Understand Continuity Definition

A function f(x)f(x) is continuous at a point x=ax=a if the limit of the function as xx approaches aa exists and is equal to the function's value at aa. This means three conditions must be met: f(a)f(a) must be defined, lim⁡x→af(x)\lim_{x \to a} f(x) must exist, and these two values must be equal.

Step 2: Evaluate the Function Value

For the given constant function f(x)=kf(x)=k, the value of the function at any point x=ax=a is simply kk. This means the function is defined for all real numbers.

Step 3: Evaluate the Limit

The limit of a constant function as xx approaches any value aa is always the constant itself. This is because the function's value does not change with xx.

Step 4: Compare Function Value and Limit

Comparing the function value f(a)f(a) and the limit lim⁡x→af(x)\lim_{x \to a} f(x), we find that both are equal to kk. This satisfies the condition for continuity.

Step 5: Conclusion

Since the continuity condition holds true for any arbitrary real number aa, the constant function f(x)=kf(x)=k is continuous at all points in its domain, which is all real numbers.

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