Chapter 9 and 11 Flashcards
the derivative of a function f : R → R
f’: S→R
f’= lim y→x f(y)-f(x)/y-x
K is a D-Domain and f: K→R is differentiable at x.
x is differentiable if there exists an f(x)= r:K→R and f’(x)=R s.t.
2 conditions (Theorem 9.2.2)
- lim x→0 r(y)/y-x =0
2. for all y in K, f(y)=f’(x)(y-x)+f(x)+r(y)
Rolle’s Theorem. Usual setup. Assume a<b></b>
- f(a)=f(b)
2.f is continuous on [a,b]
3.f is differentiable on (a,b) then
There exists a c in (a,b) s.t. f’(c)=0
Mean Value Theorem
Usual setup. Let a,b be elements of R s.t. [a,b] is contained in K. Sps f is continuous on [a,b] and differentiable on (a,b). Then, there exists a c in [a,b] s.t. f’(c)=f(b)-f(a)/b-a
Darboux’s Theorem
Let K be a D-Domain and f be differentiable on [a,b] contained in K. Then, f’ satisfies the IVP on [a,b]
a Riemann sum for a function f corresponding to a partition P
For a function f defined on [a, b], a partition P of [a, b] into a
collection of subintervals [x0, x1], [x1, x2], · · · , [xn−1, xn], and for each i = 1, 2, · · · , n, a point x∗i in [xi−1, xi] the sum of f(x∗i)(xi − xi−1) from i=1 to n is call a ________ _____ for f determine by the partition P. Let |P| = max {xi − xi−1 for all
i = 1, 2, · · · , n} denote the longest length of all the subintervals.
the Riemann integral of a function f over [a, b]
For all epsilon greater than 0 there exists a delta s.t. if |||P||-0|
D-Domain
a subset K contained in R is a _________ if K is the union of countably many “non-degenerate” disjoint intervals
differentiable at a point
Let K be a D-Domain and f: K → R, x is an element of K. f is ________ at x if the limit as y→x of f(y)-f(x)/y-x exists
differentiable on S
If f is _________ at every point in a set S contained in K, then f is _________ on S
lim x→0 r(y)/y-x=0 implies that
Lemma 9.2.4 Usual setup
r(y)→0 as y approaches x where y-x is the distance from the tangent line to the curve
If f is differentiable at x, then
f is continuous at x.
usual setup. g: K→R. f and g are differentiable at x s.t. x=k then, 3 things constant, add/subtract, product rule (Theorem 9.2.6)
- for all k in R, (kf)’(x)= k*f’(x)
- (f+ or -g)’(x)= f’(x) + or - g’(x)
- (f*g)’(x)= f’(x)g(x)+f(x)g’(x)
Chain Rule Theorem
Let K and K’ be D-Domains. Sps f: K→R and g: K’→R. f[K] is contained in K’
Chain Rule. Sps f is differentiable at x in K and g is differentiable at f(x) then
the derivative of the composition of f in g(x) =g’(f(x))*f’(x)
Let (a,b) be elements of R. Let f: (a,b)→R and a constant function. Then,
the derivative at x is 0 for all x in (a,b)
Global maximum
Let X be a metric space, f:X→R, z be an element of X. Then, f(z) is a __________ for a function f if f(z) is greater than or equal to f(x) for all x in X
Global minimum
Let X be a metric space, f:X→R, z be an element of X. Then, f(z) is a __________ for a function f if f(z) is less than or equal to f(x) for all x in X
Local maximum
for f if there exists an r>0 s.t. f(z) is greater than or equal to f(x) for all x in an open ball radius r about z
Local minimum
for f if there exists an r>0 s.t. f(z) is less than or equal to f(x) for all x in an open ball radius r about z
Local Extreme Theorem (9.4.2)
Usual setup. If f is differentiable at some c in intK where c is a local extremum, then f’(c)=0
Interior
open ball around x fully contained in the set
Corollary of the MVT. Usual setup. Let I be contained in K be an interval. Then
f is constant iff its derivative is 0 for all x in I
Usual setup. Let I be an interval in K. g:K→R. Then, (Corollary 9.4.8)
f’(x)=g’(x) for all x in I iff f(x)=g(x)+c where c is constant
Antiderivative
Let K be a D-Domain. F: K→R is an _______ for f:K→R if F’(x)=f(x) for all x in K
Corollary 9.4.8 implies that if f has an antiderivative then
it has infinitely many
Theorem 9.5.2 Usual setup interval I is contained K. Sps f is differentiable on I. Then, 2 things
- f is increasing on I iff f’(x) is greater than or equal to 0
- f is decreasing on I iff f’(x) is less than or equal to 0
Theorem 9.5.3 Usual setup. Let K be a D-Domain. f: K→R is differentiable on [a,b] contained in K . If f’(x) is not 0 for all x in [a,b], then
f is injective on the closed interval
Lemma 9.5.4 Let K be a D-domain, f is differentiable on [a,b] contained in K. If f’(a) and f’(b) are opposite signs, then
there exists a c in (a,b) s.t. f’(c)=0
Intermediate Value Property
Let I be an interval on R. f: I→R has the _____ ______ _____ if for all a and b in I and N is b/w f(a) and f(b) then there exists a c in I s.t. f’(c)=N
Uniqueness of the Integral
Let a<b></b>
||P|| Mesh
maximum size of subintervals because the widths of the subintervals can be different
Let a<b></b>
a) the integration of f from c to c is defined to be 0
b) the negative integration of f from b to a
Let a<b></b>
f is bounded because the range is a bounded set
Translation Invariance Theorem
Let a<b></b>