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math104-s21:s:dingchengyang [2021/05/09 18:07]
73.132.71.37
math104-s21:s:dingchengyang [2026/02/21 14:41] (current)
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 8. Let a1 be any real number satisfying 0 < a1 < 1 , and define a2, a3, . . . recursively via an+1 := cos(an). Why would this sequence be monotone? I plugged a0 = 0.5 into my calculator and it is clearly not monotone. If so, how should we prove that this sequence converges?\\ 8. Let a1 be any real number satisfying 0 < a1 < 1 , and define a2, a3, . . . recursively via an+1 := cos(an). Why would this sequence be monotone? I plugged a0 = 0.5 into my calculator and it is clearly not monotone. If so, how should we prove that this sequence converges?\\
 9. What is an efficient way, if any, to test uniform convergence and uniform continuity?\\ 9. What is an efficient way, if any, to test uniform convergence and uniform continuity?\\
 +10. Is it true that if F is differentiable then it is integrable and vice versa?\\
 +11. What does the notation: Sum{from n=1 to infinity}fn converges uniformly mean?\\
 +12. Determine whether sum{n=1,inf} 1/(n+0.5) converges or diverges?\\
 +13: Let f : [a, b] → R be a Riemann integrable function. Let g : [a, b] → R be a
 +function such that {x ∈ [a, b]; f(x) = g(x)} is finite. Show that g(x) is Riemann integrable and the integral of f(x) on [a,b] is equal to that of g(x). Does the conclusion still hold when {x ∈ [a, b]; f(x) = g(x)} is countable?\\
 +14: When do we have equality in the inequality |integral f| < = integral |f| ?\\
 +15: What are ways of proving connectedness?\\
 +16: What is the epsilon room proof?\\
 +17: What are good strategies to coming up with the right partitions for integration proofs?\\
 +18: Why is change of variables useful? And what is its general form?\\
 +19: What is the Second Mean Value Theorem for Integrals?\\
 +20: Is the boundary of an open ball always a sphere?\\
 +21: What is the difference between discrete metric and continuous metric?\\
 +22: What does the iota function mean?\\
 +23: How can we apply change of variables to usub?\\
 +24: In usub, I don't remember that u needs to be strictly increasing. But in the requirement of change of variables, phi needs to be strictly increasing. How should we explain this?\\
 +25: When can we not use Lopital's Rule?\\
 +26: Is the set [0,1]∩Q compact or not? (from mt2)\\
 +27: For the radius of convergence for power series, we used a similar approach of root test. Is there a ratio test analog of this proof?\\
 +28: Is it true that uniform convergence preserves integration in general? What about pointwise convergence?\\
 +29: Is it true that uniform convergence preserves derivatives in general? What about pointwise convergence?\\
 +30: What does the alpha function mean in the context of integration?\\
 +31: How to test if taylor's expansion would fail or not?\\
 +32: What does the step function mean in the context of integration? What about the infinite sum of step function?\\
 +33: How to do decimal digit expansion?\\
 +34: Why is Archimedian property useful?\\
 +35: What is exactly a topology? Is it just an abstract space consist of open and closed sets?\\
 +36: How to show a space is complete?\\
 +37: What are the implications of dense subsets?\\
 +38: Let f : [a, b] → R be a continuous function. Show that there exists c ∈ (a, b)\\
 +such that integral from a to b of f(x)dx = f(c).\\
 +39: Discuss the convergence or divergence of the Bertrand Integrals (problem 7.21 from problem book.\\
 +40: What are some techniques of picking epislon and delta? Is this mostly a reverse-engineering process?\\
 +41: What are the necessary conditions for a function to be integrable? and differentiable?\\
 +42: What are efficient ways to prove discontinuity?\\
 +43: Is the criterion for induced metric always valid? When might induced metric not be useful?\\
 +44: Prove that if the function f : I → R has a bounded derivative on I, then f is\\
 +uniformly continuous on I. Is the converse true? What is the relationship between differentiability and uniform continuity?\\
 +45: Show that the equation ex = 1 − x has one solution in R. Find this solution.\\
 +46: Let f : [0,∞) → R differentiable everywhere. Assume that limx→∞ f(x)+f(x) = 0.Show that limx→∞ f(x) = 0.\\
 +47: Prove that if c is an isolated point in D, then f is automatically continuous at c.\\
 +48: Let f(x) = x sin(1/x) for x = 0 and f(0) = 0. Prove that f is continuous at\\
 +x = 0\\
 +49: Find an example of a function that is discontinuous at every real number.\\
 +50: Find an example of a function f discontinuous on Q and another function g\\
 +discontinuous at only one point, but g ◦ f is nowhere continuous.\\
 +51: Let f(x)=[x] be the greatest integer less than or equal to x and let g(x) = x−[x].\\
 +Sketch the graphs of f and g. Determine the points at which f and g are continuous.\\
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math104-s21/s/dingchengyang.1620583672.txt.gz · Last modified: 2026/02/21 14:44 (external edit)