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<b>Statement 1:</b> f(x)=x^(3) is a one-...

Statement 1: `f(x)=x^(3)` is a one-one function.
Statement 2: Any monotonic function is a one-one function.

A

(a) Statement 1 and Statement 2 are true and Statement 2 is the correct explanation for Statement 1.

B

(b) Statement 1 and Statement 2 are true but Statement 2 is not the correct explanation for Statement 1.

C

(c) Statement 1 is true but Statement 2 is false

D

(d) Statement 2 is true but Statement 1 is false

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to analyze both statements regarding the function \( f(x) = x^3 \). ### Step 1: Verify Statement 1 We need to determine if \( f(x) = x^3 \) is a one-one function. A function is one-one (injective) if for any two values \( x_1 \) and \( x_2 \), if \( f(x_1) = f(x_2) \), then it must imply that \( x_1 = x_2 \). 1. Assume \( f(x_1) = f(x_2) \). \[ x_1^3 = x_2^3 \] 2. Taking the cube root of both sides, we get: \[ x_1 = x_2 \] Since \( x_1 = x_2 \) whenever \( f(x_1) = f(x_2) \), we conclude that \( f(x) = x^3 \) is indeed a one-one function. ### Step 2: Verify Statement 2 Statement 2 states that any monotonic function is a one-one function. A function is monotonic if it is either entirely non-increasing or non-decreasing. 1. To check if \( f(x) = x^3 \) is monotonic, we can find its derivative: \[ f'(x) = 3x^2 \] 2. The derivative \( f'(x) = 3x^2 \) is always greater than or equal to 0 for all \( x \) (since squares are non-negative). Specifically, \( f'(x) > 0 \) for all \( x \neq 0 \). 3. Since the derivative is non-negative and only equals zero at \( x = 0 \), the function is monotonically increasing everywhere. ### Conclusion Since \( f(x) = x^3 \) is a one-one function and it is also a monotonic function (specifically, monotonically increasing), both statements are true. Additionally, Statement 2 correctly explains Statement 1. ### Final Answer Both Statement 1 and Statement 2 are true, and Statement 2 is a correct explanation for Statement 1.
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