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Let A = R -{3} " and " B =R -{1}. " Then...

Let `A = R -{3} " and " B =R -{1}. " Then " f : A to B : f (x) = ((x-2))/((x-3))` is

A

one-one and into

B

one -one and onto

C

many-one and into

D

many -one and onto

Text Solution

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To solve the given problem, we need to analyze the function \( f(x) = \frac{x - 2}{x - 3} \) defined from the set \( A = \mathbb{R} - \{3\} \) to the set \( B = \mathbb{R} - \{1\} \). We want to determine if the function is one-to-one (injective) and onto (surjective). ### Step 1: Check if the function is one-to-one (injective) To check if the function is one-to-one, we need to show that if \( f(x_1) = f(x_2) \), then \( x_1 = x_2 \). 1. Start with the equation: \[ f(x_1) = f(x_2) \] This means: \[ \frac{x_1 - 2}{x_1 - 3} = \frac{x_2 - 2}{x_2 - 3} \] 2. Cross-multiply: \[ (x_1 - 2)(x_2 - 3) = (x_2 - 2)(x_1 - 3) \] 3. Expand both sides: \[ x_1 x_2 - 3x_1 - 2x_2 + 6 = x_2 x_1 - 3x_2 - 2x_1 + 6 \] 4. Simplifying gives: \[ -3x_1 - 2x_2 = -3x_2 - 2x_1 \] 5. Rearranging terms: \[ -3x_1 + 2x_1 = -3x_2 + 2x_2 \] \[ -x_1 = -x_2 \] 6. Thus, we conclude: \[ x_1 = x_2 \] This proves that \( f \) is one-to-one. ### Step 2: Check if the function is onto (surjective) To check if the function is onto, we need to show that for every \( y \in B \), there exists an \( x \in A \) such that \( f(x) = y \). 1. Set \( f(x) = y \): \[ \frac{x - 2}{x - 3} = y \] 2. Cross-multiply: \[ x - 2 = y(x - 3) \] 3. Expand and rearrange: \[ x - 2 = yx - 3y \] \[ x - yx = -3y + 2 \] \[ x(1 - y) = -3y + 2 \] 4. Solve for \( x \): \[ x = \frac{-3y + 2}{1 - y} \] 5. We need to ensure that \( x \) is in \( A \) (i.e., \( x \neq 3 \)): \[ \frac{-3y + 2}{1 - y} \neq 3 \] 6. Solve the inequality: \[ -3y + 2 \neq 3(1 - y) \] \[ -3y + 2 \neq 3 - 3y \] This is always true since both sides will simplify to the same expression. Thus, for every \( y \in B \), there exists an \( x \in A \) such that \( f(x) = y \). Therefore, \( f \) is onto. ### Conclusion Since we have shown that \( f \) is both one-to-one and onto, we conclude that the function \( f: A \to B \) is bijective. ### Final Answer The function \( f(x) = \frac{x - 2}{x - 3} \) is both one-to-one and onto. ---

To solve the given problem, we need to analyze the function \( f(x) = \frac{x - 2}{x - 3} \) defined from the set \( A = \mathbb{R} - \{3\} \) to the set \( B = \mathbb{R} - \{1\} \). We want to determine if the function is one-to-one (injective) and onto (surjective). ### Step 1: Check if the function is one-to-one (injective) To check if the function is one-to-one, we need to show that if \( f(x_1) = f(x_2) \), then \( x_1 = x_2 \). 1. Start with the equation: \[ ...
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