Difficult Question in Calculus — limits and integrals

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The discussion revolves around proving a statement related to continuous functions using limits and integrals. The original poster has attempted various methods, including L'Hôpital's Rule and integral reduction formulas, but has not found success. A suggestion is made to consider the case of step functions as a potential starting point for the proof. Additionally, a method involving the maximum value of the function and limits of integrals is proposed, emphasizing the need to establish both upper and lower bounds. The conversation highlights the complexity of the problem and the need for a structured approach to proof.
omeraz100
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Homework Statement


file.php?id=21.png

(hebrew) : f(x) a continuous function. proof the following

Homework Equations


I guess rules of limits and integrals

The Attempt at a Solution


I've tried several approaches:
taking ln() of both sides and using L'Hospitale Rule.
Thought about using integral reduction formula.
But really nothing even got me close.
Looking forward to any advice
 
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omeraz100 said:

Homework Statement


file.php?id=21.png

(hebrew) : f(x) a continuous function. proof the following

Homework Equations


I guess rules of limits and integrals

The Attempt at a Solution


I've tried several approaches:
taking ln() of both sides and using L'Hospitale Rule.
Thought about using integral reduction formula.
But really nothing even got me close.
Looking forward to any advice
Please show us at least some of what you've tried. Per forum rules, you must show an attempt.
 
omeraz100 said:

Homework Statement


file.php?id=21.png

(hebrew) : f(x) a continuous function. proof the following

Homework Equations


I guess rules of limits and integrals

The Attempt at a Solution


I've tried several approaches:
taking ln() of both sides and using L'Hospitale Rule.
Thought about using integral reduction formula.
But really nothing even got me close.
Looking forward to any advice

If I were doing it would let
M = \max_{x \in [a,b]} |f(x)|, \; L_t = \left( \int_a^b |f(x)|^t \, dx \right)^{1/t},
then I would show that: (1) ## \lim_{t \to \infty} L_t \leq M##; and (2) ##\lim_{t \to \infty} L_t \geq M##.

(1) is quite easy; (2) is a bit trickier and needs some properties of continuous functions on finite, closed intervals.
 
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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