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Statement-1: f(x ) = log( cosx)sinx is w...

Statement-1: `f(x ) = log_( cosx)sinx` is well defined in `(0,pi/2)`.
and Statement:2 sinx and cosx are positive in `(0,pi/2)`

A

Statement-1 is true, Statement-2 is true, Statement-2 is a correct explanation for statement-2

B

Statement-1 is true, Statement-2 is true, Statement-2 is not a correct expanation for statement-2

C

Statement-1 is True, Statement-2 is false

D

Statement-1 is False, Statement-2 is true

Text Solution

AI Generated Solution

The correct Answer is:
To determine whether the statements are true, we will analyze each statement step by step. ### Step 1: Analyze Statement 1 The function given is \( f(x) = \log_{\cos x}(\sin x) \). We need to check if this function is well-defined in the interval \( (0, \frac{\pi}{2}) \). #### Conditions for the logarithm: 1. The argument of the logarithm must be positive: \( \sin x > 0 \). 2. The base of the logarithm must be positive and not equal to 1: \( \cos x > 0 \) and \( \cos x \neq 1 \). ### Step 2: Check the conditions in the interval \( (0, \frac{\pi}{2}) \) - **For \( \sin x > 0 \)**: - In the interval \( (0, \frac{\pi}{2}) \), \( \sin x \) is positive since \( \sin x \) increases from 0 to 1. - **For \( \cos x > 0 \)**: - In the interval \( (0, \frac{\pi}{2}) \), \( \cos x \) is also positive since \( \cos x \) decreases from 1 to 0. - **For \( \cos x \neq 1 \)**: - At \( x = 0 \), \( \cos(0) = 1 \), but since we are considering the open interval \( (0, \frac{\pi}{2}) \), this condition is satisfied. ### Conclusion for Statement 1: Since both conditions are satisfied in the interval \( (0, \frac{\pi}{2}) \), **Statement 1 is true**. ### Step 3: Analyze Statement 2 Statement 2 claims that \( \sin x \) and \( \cos x \) are positive in the interval \( (0, \frac{\pi}{2}) \). - **For \( \sin x \)**: - As discussed, \( \sin x \) is positive in the interval \( (0, \frac{\pi}{2}) \). - **For \( \cos x \)**: - Similarly, \( \cos x \) is also positive in the interval \( (0, \frac{\pi}{2}) \). ### Conclusion for Statement 2: Since both \( \sin x \) and \( \cos x \) are positive in the interval \( (0, \frac{\pi}{2}) \), **Statement 2 is also true**. ### Final Conclusion: Both statements are true. ---
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