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f is continuous ⇒ ❶ f is integrable ❷ f(x)ᐃx is differentiable ❸ (f(x)ᐃx)ᐁx = f
 
7101 Partition
Let [a,b] be a given finite interval. A partition P of [a,b] is a finite set of points {x₀,x₁,x₂,...,xₙ} satisfying a=x₀<x₁<x₂<...<xₙ=b.
9727#9750 SIBLINGS CHILDREN 9750
 
7102 Upper & Lower Sum
ᐥThe upper sum of a function f relative to a partition P is defined by 「sup(f(x))ƧP[a,b]」 The lower sum of a function f relative to a partition P is defined by 「inf(f(x))ƧP[a,b]」.ᐥ ┄ U(P) = 「S⸤i⸥(x⸤i⸥−x⸤i−1⸥) Σi=0,n」 where S⸤i⸥ = sup{f(x):x⸤i−1⸥≤x≤x⸤i⸥} ...
9727#9751 SIBLINGS CHILDREN 9751
 
7103 Riemann integrable
ᐥA function f defined and bounded on [a,b] is Riemann integrable on [a,b] if and only if inf「sup(f(x))Ƨ[a,b]」 = sup「inf(f(x))Ƨ[a,b]」 . The common value is denoted by f(x)ᐃx「a,b」.ᐥ ┄ inf{U:U=「sup{f(x):x⸤i−1⸥≤x≤x⸤i⸥}·(x⸤i⸥−x⸤i−1⸥) Σi=0,n」} = sup{L:L=「inf{f ...
9727#9753 SIBLINGS CHILDREN 9753
 
7105 Riemann's condition
ᐥLet f be defined and bounded on [a,b]. Then f is Riemann integrable on [a,b] if and only if for every ε>0 there exists a partition P of [a,b] such that inf「sup(f(x))ƧP[a,b]」 − sup「inf(f(x))ƧP[a,b]」 < ε.ᐥ
9727#9754 SIBLINGS CHILDREN 9754
 
7106
If f is monotone on [a,b] then f is Riemann integrable on [a,b].
9727#9160 SIBLINGS CHILDREN 9160
 
7107 Uniform Continuity
A function f defined on the interval [a,b] is uniformly continuous if for any given ε>0 there exist a δ>0 such that for all x,y∈[a,b] |x−y|<δ ⇒ |f(x)−f(y)|<ε .
9727#9454 SIBLINGS CHILDREN 9454
 
7111 Fundamental theorem of calculus
If f is Riemann integrable on [a,b] then f(t)ᐃt「a,x」 is continuous on [a,b]. Further more, f is continuous on [a,b] then f(t)ᐃt「a,x」 is differentiable on [a,b] and (f(t)ᐃt「a,x」)ᐁx=f.
9727#9755 SIBLINGS CHILDREN 9755
 
Songs in Easy English
 
718
Let f be defined and continuous on [a,b]. Then f is uniformly continuous on [a,b].
9727#9764 SIBLINGS CHILDREN 9764
 
Fundamental theorem of calculus
f is continuous at c if and only if for every ε>0 there exists δ>0 such that |x−c|<δ ⇒ |f(x)−f(c)|<ε. ┄ Continuous at c 「f(x) Ƚx→c」 = f(c) ┄ A function f:A→ℝ is differentiable at c if and only if 「(f(x)−f(c))/(x−c) Ƚx→c」 exists. The value of the limit, c ...
9727#9759 SIBLINGS CHILDREN 9759
 
Riemann Integration
9727#9728 SIBLINGS CHILDREN 9728
 
Riemann sum
9727#4930 SIBLINGS CHILDREN 4930

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