Pure Mathematics F3: Integration
17 flashcards · Mathematics · by lakesare
Visually imagine: discontinuous function that can be integrated discontinuous function that can NOT be integrated.
can be integrated can NOT be integrated Dirichlet function We can always assign a value to the area between the graph and the x-axis for a continuous function defined on a closed interval. You will also see that we can do the same for the function in (a), but not for the function in (b).
Supremum of a set - sup(E) VS supremum of a function - sup(f)?
Sup(f) is a supremum of the image set of f. The concepts of the supremum of a real function and the supremum of a set of real numbers are related in the following way: the supremum of a function is the supremum of the image set of the function.
How does this notation expand?
What's inf(f)?
inf(f) = –1
[Partition of an interval] Visually imagine the partition P of [a, b].
[Partition of an interval] Visually imagine δxi.
δxi is the length of xi–1... xi subinterval.
[Partition of an interval] What's ║P║ called?
Mesh of P.
[Partition of an interval] What's a mesh of P?
The length of the largest subinterval.
[Partition of an interval] Partition VS standard partition of an interval?
partition - different sizes standard partition - equal sizes
[Riemann Integral] Visually imagine the Lower Riemann Sum.
[Riemann Integral] What's Mi and δxi in the upper Riemann sum definition?
Mi - supremum of f on this interval δxi - length of this interval
[Riemann Integral] What do we call these areas?
Lower Riemann sum - L(f, P) Upper Riemann sum - U(f, P)
[Riemann Integral] What's shocking about Lower and Upper Riemann sums?
No matter what the partitions are - L(f, P) is always smaller than U(f, P')!
[Riemann Integral] What do we call a and b?
Limits of integration.
[Riemann Integral] Lower Riemann Sum VS Lower Riemann Integral
Lower Riemann Sum - colored area Lower Riemann Integral - the largest area among all partitions
[Riemann Integral] What's P in the definition of a lower integral?
All possible partitions!
[Integrals] Name 2 famous ways to define integration.
Riemann integration - vertical rectangles Lebesgue integration - horizontal rectangles