A question about limit of a continuous function

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The discussion centers on justifying the inequality |lim(x-->0)(f(x))|≤lim(x-->0)|f(x)| for a continuous function f. Participants emphasize the continuity of the absolute value function, which aids in understanding the limit properties. It is clarified that since the absolute value is continuous, |lim(x-->0)(f(x))| equals lim(x-->0)|f(x)|. The original poster ultimately resolves their question by referencing a theorem from their textbook. The conversation highlights the importance of continuity in limit evaluations.
mike1988
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I am trying to solve a question and I need to justify a line in which |lim(x-->0)(f(x))|≤lim(x-->0)|f(x)| where f is a continuous function.

Any help?
 
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The absolute value is a continuous function. That is:

|\ |:\mathbb{R}\rightarrow \mathbb{R}:x\rightarrow |x|

is continuous. Does that help?? What do you know about continuity and limits?
 
mike1988 said:
I am trying to solve a question and I need to justify a line in which |lim(x-->0)(f(x))|≤lim(x-->0)|f(x)| where f is a continuous function.

Any help?

Show your work. Where are you stuck?

RGV
 
Ray Vickson said:
Show your work. Where are you stuck?

RGV

actually I figured this out. Since || is a continuous, |lim(x-->0)(f(x))|= lim(x-->0)|f(x)| which is obvious from one of the theorems in my book.

Thanks though!
 
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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