MIT OpenCourseWarehttp://ocw.mit.edu 18.102 Introduction to Functional Analysis Spring 2009 For information about citing these materials or our Terms of Use, visit: http://ocw.mit.edu/terms.� TOPICS FOR THE FIRST TEST FOR 18.102, SPRING 2009 TEST: THURSDAY 5 MARCH, RICHARD MELROSE Completeness of answers will be taken strong into account on the test. You are supposed to get things really right! 1. Question 1 Will be on proving some property of integrable functions directly from the def-inition. Thus, just assuming that f is integrable (you will be asked to give the definition accurately) show that |f|, Re f, Im f, (Re f)+ (the positive part) or f + g for two integrable functions, or max(f, g) for two real integrable functions or some such. 2. Question 2 Monotonicity for step functions. I will ask you to prove one of the two basic monotonicity results for step functions – e.g. that if fn is an increasing sequence with non-negative pointwise limit then lim fn ≥ 0 (including possibly +∞.) Or the result on which this depends. 3. Question 3 I suggested I might ask you to prove the continuity-in-the-mean of L1 functions. That is to show that � lim ft − f = 0 t→0 | | for any f ∈ L1 . 4. Question 4 There probably will be no question 4, if there is, it would be about null functions. Department of Mathematics, Massachusetts Institute of Technology 1
View Full Document