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Let f(x)=|x-2|, then...

Let `f(x)=|x-2|`, then

A

`f(x^(2))=(f(x))^(2)`

B

`f(x+y)=f(x)f(y)`

C

`f(|x|)=|f(x)|`

D

none of these

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to analyze the function \( f(x) = |x - 2| \) and check the validity of the following options: 1. \( f(x^2) \) vs \( f(x)^2 \) 2. \( f(x+y) \) vs \( f(x) \cdot f(y) \) 3. \( f(|x|) \) vs \( |f(x)| \) Let's evaluate each option step by step. ### Step 1: Evaluate \( f(x^2) \) and \( f(x)^2 \) 1. **Calculate \( f(x^2) \)**: \[ f(x^2) = |x^2 - 2| \] 2. **Calculate \( f(x)^2 \)**: \[ f(x) = |x - 2| \implies f(x)^2 = (|x - 2|)^2 = (x - 2)^2 \] 3. **Compare \( f(x^2) \) and \( f(x)^2 \)**: - \( f(x^2) = |x^2 - 2| \) - \( f(x)^2 = (x - 2)^2 \) These two expressions are not equal for all \( x \). For example: - If \( x = 0 \): \[ f(0^2) = |0 - 2| = 2 \quad \text{and} \quad f(0)^2 = (|0 - 2|)^2 = 4 \] - If \( x = 3 \): \[ f(3^2) = |9 - 2| = 7 \quad \text{and} \quad f(3)^2 = (|3 - 2|)^2 = 1 \] Thus, **Option 1 is incorrect**. ### Step 2: Evaluate \( f(x+y) \) and \( f(x) \cdot f(y) \) 1. **Calculate \( f(x+y) \)**: \[ f(x+y) = |(x+y) - 2| = |x + y - 2| \] 2. **Calculate \( f(x) \cdot f(y) \)**: \[ f(x) = |x - 2| \quad \text{and} \quad f(y) = |y - 2| \implies f(x) \cdot f(y) = |x - 2| \cdot |y - 2| \] 3. **Compare \( f(x+y) \) and \( f(x) \cdot f(y) \)**: - For \( x = 0 \) and \( y = 0 \): \[ f(0 + 0) = |0 - 2| = 2 \quad \text{and} \quad f(0) \cdot f(0) = 2 \cdot 2 = 4 \] - For \( x = 2 \) and \( y = 2 \): \[ f(2 + 2) = |4 - 2| = 2 \quad \text{and} \quad f(2) \cdot f(2) = 0 \cdot 0 = 0 \] Thus, **Option 2 is incorrect**. ### Step 3: Evaluate \( f(|x|) \) and \( |f(x)| \) 1. **Calculate \( f(|x|) \)**: \[ f(|x|) = ||x| - 2| \] 2. **Calculate \( |f(x)| \)**: \[ |f(x)| = ||x - 2| | = |x - 2| \quad \text{(since absolute value is always non-negative)} \] 3. **Compare \( f(|x|) \) and \( |f(x)| \)**: - For \( x = 3 \): \[ f(|3|) = |3 - 2| = 1 \quad \text{and} \quad |f(3)| = |1| = 1 \] - For \( x = -3 \): \[ f(|-3|) = |3 - 2| = 1 \quad \text{and} \quad |f(-3)| = |(-3 - 2)| = 5 \] Thus, **Option 3 is incorrect**. ### Conclusion Since all options are incorrect, the final answer is: **None of these options are correct.**
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