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math104-s21:s:dingchengyang [2021/05/09 21:23]
73.132.71.37
math104-s21:s:dingchengyang [2026/02/21 14:41] (current)
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 13: Let f : [a, b] → R be a Riemann integrable function. Let g : [a, b] → R be a 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?\\ 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.1620595418.txt.gz · Last modified: 2026/02/21 14:44 (external edit)