Find the limit of ln (sinx) as x approaches pi

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The limit of ln(sin(x)) as x approaches π from the left involves understanding the behavior of sin(x) near π. As x approaches π, sin(x) approaches 0 from the positive side. Consequently, ln(sin(x)) approaches negative infinity since the natural logarithm of a value approaching zero is undefined and trends downward. The discussion clarifies that the squeeze theorem is not applicable in this case; instead, the focus is on the direct limit of ln(sin(x)). Overall, the limit is confirmed to be negative infinity.
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I need to find the limit of. Ln (sinx) as x approaches pi-, that is, as x approaches pi from the left.

I thought I should use the squeeze theorem, but I am not sure how to apply it. My teacher is not requiring us to use the delta/Epsilon method, so I am sure it is a squeeze method. But how do I set it up?

I tried -1 < sinx < 1,
Thus ln (-1) < ln (sinx) < ln (1)

But you can't take the ln of a negative... please help.
 
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What can you say about \sin(x) as x \rightarrow \pi^-? Is it positive or negative? What value does it approach?
 
As x aproaches pi from the left your sine function aproaches 0. This means this is equivalent of finding the limit as the thing inside the natural log aproaches 0. Its very easy limit.
 
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Oh. So this isn't squeeze action... I just find the limit of ln as sinx approaches zero. Hmm... I would need to graph that. But that should be simple enough. Tjanks guys
 
essedbl said:
Oh. So this isn't squeeze action... I just find the limit of ln as sinx approaches zero. Hmm... I would need to graph that.
Good idea. Remember that x is approaching π from the left, which says something about how sin(x) is approaching zero, and finally, what ln(sin(x)) is doing.
essedbl said:
But that should be simple enough. Tjanks guys
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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