Real Numbers

Let , and .

upper bound lower bound bounded if it has both lower and upper bound maximum upper bound and minimum lower bound and supremum , infimum ,

Axiom of Completeness a nonempty set of real numbers has an or if it is bounded below or above

Archimedean Property ,

Nested Interval Property

Sequences

converges if , or bounded if Cauchy if monotone if

Monotone Convergence a monotone bounded sequence is convergent

Bolzano-Weierstrass a bounded sequence has a convergent subsequence

Topology

Let

limit point , isolated point is not a limit point

open closed is open, contains all its limit points compact Heine-Borel Theorem

  • is bounded and closed
  • Every open cover of has a finite subcover

closure the union of with its limit points

connected perfect every point of is a limit point.

Union of arbitrarily many open sets is open. Union of finitely many closed sets is closed. Intersection of arbitrarily many closed sets is closed. Intersection of finitely many open sets is open.

Functions

Let

continuous

uniformly continuous

monotone composition for continuous, is continuous compactness compact then compact. connectedness connected then connected.

Extreme Value Theorem

Intermediate Value Theorem , .

Derivative

Differentiability Let . For , the derivative of at is . If this exists, then is differentiable at . If exists for all , then is differentiable on .

If is differentiable at , then it is continuous at .

Sequential Criterion differentiable at if and only if , implies converges

has a relative extrema at if where implies is an upper or lower bound for

If exists and is a relative extrema, then

Interior Extremum Theorem Let be differentiable on . If has max or min value at , then .

Darboux Theorem If differentiable on and , then there is where .

Rolle’s Theorem Let differentiable on . If , then there is a point where .

Mean Value Theorem If is continuous on and differentiable on , then there exists such that

Generalized Mean Value Theorem If and are continuous, then