MA 511 A1 — Fall 2011
Introduction to Analysis I
REVIEW SHEET
Definitions
- order, ordered set
- bounded above, upper bound
- least upper
bound
- field
- ordered field
- one-to-one, onto, bijection
- finite, infinite,
countable, uncountable
- equivalence relation
- metric space
-
Nr(x)
- open set
- limit point
-
closed set
- closure of a set
- interior of a set
- bounded set
- open cover
- compact set
- discrete metric
- convergent sequence
- Cauchy sequence
- convergent series
- f:X-->Y is continuous at p
- f:X-->Y, A subset of X -- define f(A)
- f:X-->Y, B subset of Y -- define f^{-1}(B)
- lim_{x-->p} f(x) = L
- differentiable
- local max/min
Theorems from class that you should know how to prove:
- Square root of two is irrational.
- x+y = x+z implies y=z.
- 0x=0
- x>0, y < z implies xy < xz
- Z is unbounded in R (without assuming the Archidean principle)
- sup (0,1) = 1
- Nr(x) is an open set.
- U is open if and only if Uc is closed.
- Arbitrary unions of opens are open.
- Finite intersections of opens are open.
- Analogous statements for closed sets.
- F closed and E a subset of F implies E is contained in F.
- Proving particular sequences converge directly from the definition
(e.g. 1/n → 0, 1/n2 → 0, ...).
- Limits are unique.
- If E is closed, pn in E for all n and pn →
p, then p is in E.
- If {s_n} → s and {t_n} → t, then {s_n+t_n} → s+t.
- Compact implies closed.
- Compact implies bounded.
- A descending sequences of non-empty compact sets has a non-empty
intersection.
- If K is compact and covered by an ascending sequence of open sets,
then K is covered by a single open set.
- Convergent implies Cauchy.
- A closed subset of a compact set is compact.
- Cauchy sequences are bounded.
- K compact and infinite implies that K has a limit point.
- If Σ an is convergent, then an tends
to
0.
- Comparison test (Theorem 3.25)
- f,g continuous implies f+g is continuous
- f:X-->Y continuous, U open in Y implies f^{-1}(U) is open in X.
- f:X-->Y continuous, K compact in X implies f(K) compact
- Extreme value theorem
- differentiable implies continuous
- (f+g)' = f' + g'
- product rule
- local min/max at p implies f'(p)=0
- Rolle's
theorem
-- that is, f(a)=f(b), f differentiable implies f'(c)=0 for c between a and b
- Mean value theorem
- f'=0 implies f is constant
- f'>0 implies f is increasing
- f'<0 implies f is decreasing