Math Problem Statement

Diketahui fungsi f(x) = (2x - 4) / (2 - x). Berikut adalah pernyataan yang benar ...

Solution

The given function is:

f(x)=2x42xf(x) = \frac{2x - 4}{2 - x}

Now, let's analyze the statements to determine which are correct.

Step 1: Simplify the function

We can simplify f(x)f(x):

f(x)=2(x2)2xf(x) = \frac{2(x - 2)}{2 - x}

Notice that 2x2 - x can be written as (x2)-(x - 2), so:

f(x)=2(x2)(x2)=2forx2f(x) = \frac{2(x - 2)}{-(x - 2)} = -2 \quad \text{for} \quad x \neq 2

Thus, for all x2x \neq 2, f(x)=2f(x) = -2.

Step 2: Determine if f(2)f(2) exists

At x=2x = 2, the denominator becomes zero:

f(2)=2(2)422=00f(2) = \frac{2(2) - 4}{2 - 2} = \frac{0}{0}

Since we have an indeterminate form 00\frac{0}{0}, f(2)f(2) is undefined.

Step 3: Evaluate limits around x=2x = 2

  1. Limit as x2x \to 2^-:

    • As x2x \to 2 from the left, f(x)=2f(x) = -2.
  2. Limit as x2+x \to 2^+:

    • As x2x \to 2 from the right, f(x)=2f(x) = -2.

Thus, limx2f(x)=2\lim_{x \to 2} f(x) = -2.

Step 4: Analyze the statements

  • a. Nilai f(2)f(2) tidak ada (The value f(2)f(2) does not exist): True. As shown, f(2)f(2) is undefined.
  • b. limx2f(x)=2\lim_{x \to 2} f(x) = 2: False. The correct limit is 2-2, not 2.
  • c. limx2+f(x)=2\lim_{x \to 2^+} f(x) = -2: True. The limit from the right is indeed 2-2.
  • d. \lim_{x \to 2} f(x) tidak ada (The limit as \( x \to 2 does not exist): False. The limit exists and equals 2-2.
  • e. limx2f(x)=2\lim_{x \to 2^-} f(x) = -2: True. The limit from the left is also 2-2.

Conclusion

The correct statements are: a, c, and e.

Would you like a further explanation or have any specific questions?


Here are some related questions you might find useful:

  1. How do you determine limits of a function at a point?
  2. What is the meaning of a limit from the left or right?
  3. How do you handle indeterminate forms like 00\frac{0}{0}?
  4. Why do we say a function is undefined at a point?
  5. What happens when the limit exists, but the function is undefined?

Tip: Always check the behavior of a function from both sides of a point to confirm whether the limit exists.

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Math Problem Analysis

Mathematical Concepts

Limits
Functions
Indeterminate Forms

Formulas

Limit of a function
Simplifying algebraic expressions

Theorems

Limit Theorem
Indeterminate Form Resolution

Suitable Grade Level

Grades 11-12