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Theorem List for Metamath Proof Explorer - 27301-27400   *Has distinct variable group(s)
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Statement

19.19.2  Finite multiplication of numbers and finite multiplication of functions

Theoremfmul01 27301* Multiplying a finite number of values in [ 0 , 1 ] , gives the final product itself a number in [ 0 , 1 ]. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremfmulcl 27302* If ' Y ' is closed under the multiplication of two functions, then Y is closed under the multiplication ( ' X ' ) of a finite number of functions. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremfmuldfeqlem1 27303* induction step for the proof of fmuldfeq 27304. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremfmuldfeq 27304* X and Z are two equivalent definitions of the finite product of real functions. Y is a set of real functions from a common domain T, Y is closed under function multiplication and U is a finite sequence of functions in Y. M is the number of functions multiplied together. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremfmul01lt1lem1 27305* Given a finite multiplication of values betweeen 0 and 1, a value larger than its frist element is larger the whole multiplication. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremfmul01lt1lem2 27306* Given a finite multiplication of values betweeen 0 and 1, a value larger than any multiplicand, is larger than the whole multiplication. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremfmul01lt1 27307* Given a finite multiplication of values betweeen 0 and 1, a value E larger than any multiplicand, is larger than the whole multiplication. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremcncfmptss 27308* A continuous complex function restricted to a subset is continuous, using "map to" notation. (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremfmptdf 27309* A version of fmptd 5795 using bound-variable hypothesis instead of a distinct variable condition for . (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremrrpsscn 27310 The positive reals are a subset of the complex numbers. (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremmulcncf 27311* The multiplication of two continuous complex functions is continuous. (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremmulc1cncfg 27312* A version of mulc1cncf 18623 using bound-variable hypotheses instead of distinct variable conditions. (Contributed by Glauco Siliprandi, 30-Jun-2017.)

Theoreminfrglb 27313* The infimum of a non-empty bounded set of reals is the greatest lower bound. (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremexpcncf 27314* The power function on complex numbers, for fixed exponent N, is continuous. Similar to expcn 18590. (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremeluzelcn 27315 A member of a set of upper integers is a complex number. (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremm1expeven 27316 Exponentiation of negative one to an even power. (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremexpcnfg 27317* If is a complex continuous function and N is a fixed number, then F^N is continuous too. A generalization of expcncf 27314. (Contributed by Glauco Siliprandi, 29-Jun-2017.)

19.19.3  Limits

Theoremclim1fr1 27318* A class of sequences of fractions that converge to 1 (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremisumneg 27319* Negation of a converging sum. (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremclimrec 27320* Limit of the reciprocal of a converging sequence. (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremclimmulf 27321* A version of climmul 12313 using bound-variable hypotheses instead of distinct variable conditions. (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremclimexp 27322* The limit of natural powers, is the natural power of the limit. (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremcliminf 27323* A bounded monotonic non increasing sequence converges to the infimum of its range. (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremclimsuselem1 27324* The subsequence index has the expected properties: it belongs to the same upper integers as the original index, and it is always larger or equal than the original index. (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremclimsuse 27325* A subsequence of a converging sequence , converges to the same limit. is the strictly increasing and it is used to index the subsequence (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremclimrecf 27326* A version of climrec 27320 using bound-variable hypotheses instead of distinct variable conditions. (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremclimneg 27327* Complex limit of the negative of a sequence. (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremcliminff 27328* A version of climinf 27323 using bound-variable hypotheses instead of distinct variable conditions (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremclimdivf 27329* Limit of the ratio of two converging sequences. (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremclimreeq 27330 If is a real function, then converges to with respect to the standard topology on the reals if and only if it converges to with respect to the standard topology on complex numbers. In the theorem, is defined to be convergence w.r.t. the standard topology on the reals and then represents the statement " converges to , with respect to the standard topology on the reals". Notice that there is no need for the hypothesis that is a real number. (Contributed by Glauco Siliprandi, 2-Jul-2017.)

19.19.4  Derivatives

Theoremdvsinexp 27331* The derivative of sin^N . (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremdvcosre 27332 The real derivative of the cosine (Contributed by Glauco Siliprandi, 29-Jun-2017.)

19.19.5  Integrals

Theoremioovolcl 27333 An open real interval has finite volume. (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremvolioo 27334 The measure of an open interval. (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremitgsin0pilem1 27335* Calculation of the integral for sine on the (0,π) interval (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremibliccsinexp 27336* sin^n on a closed interval is integrable. (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremitgsin0pi 27337 Calculation of the integral for sine on the (0,π) interval (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremiblioosinexp 27338* sin^n on an open integral is integrable (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremitgsinexplem1 27339* Integration by parts is applied to integrate sin^(N+1) (Contributed by Glauco Siliprandi, 29-Jun-2017.)

Theoremitgsinexp 27340* A recursive formula for the integral of sin^N on the interval (0,π) .

(Contributed by Glauco Siliprandi, 29-Jun-2017.)

19.19.6  Stone Weierstrass theorem - real version

Theoremstoweidlem1 27341 Lemma for stoweid 27403. This lemma is used by Lemma 1 in [BrosowskiDeutsh] p. 90; the key step uses Bernoulli's inequality bernneq 11392. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem2 27342* lemma for stoweid 27403: here we prove that the subalgebra of continuous functions, which contains constant functions, is closed under scaling. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem3 27343* Lemma for stoweid 27403: if is positive and all terms of a finite product are larger than , then the finite product is larger than A^M. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem4 27344* Lemma for stoweid 27403: a class variable replaces a set variable, for constant functions. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem5 27345* There exists a δ as in the proof of Lemma 1 in [BrosowskiDeutsh] p. 90: 0 < δ < 1 , p >= δ on . Here is used to represent δ in the paper and to represent in the paper. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem6 27346* Lemma for stoweid 27403: two class variables replace two set variables, for multiplication of two functions. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem7 27347* This lemma is used to prove that qn as in the proof of Lemma 1 in [BrosowskiDeutsh] p. 91, (at the top of page 91), is such that qn < ε on , and qn > 1 - ε on . Here it is proven that, for large enough, 1-(k*δ/2)^n > 1 - ε , and 1/(k*δ)^n < ε. The variable is used to represent (k*δ) in the paper, and is used to represent (k*δ/2). (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem8 27348* Lemma for stoweid 27403: two class variables replace two set variables, for the sum of two functions. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem9 27349* Lemma for stoweid 27403: here the Stone Weierstrass theorem is proven for the trivial case, T is the empty set. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem10 27350 Lemma for stoweid 27403. This lemma is used by Lemma 1 in [BrosowskiDeutsh] p. 90, this lemma is an application of Bernoulli's inequality. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem11 27351* This lemma is used to prove that there is a function as in the proof of [BrosowskiDeutsh] p. 92, (at the top of page 92): this lemma proves that g(t) < ( j + 1 / 3 ) * ε. Here is used to represent ε in the paper. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem12 27352* Lemma for stoweid 27403. This Lemma is used by other three Lemmas. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem13 27353 Lemma for stoweid 27403. This lemma is used to prove the statement abs( f(t) - g(t) ) < 2 epsilon , in [BrosowskiDeutsh] p. 92, the last step of the proof. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem14 27354* There exists a as in the proof of Lemma 1 in [BrosowskiDeutsh] p. 90: is an integer and 1 < k * δ < 2. is used to represent δ in the paper. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem15 27355* This lemma is used to prove the existence of a function as in Lemma 1 from [BrosowskiDeutsh] p. 90: is in the subalgebra, such that 0 ≤ p ≤ 1, p(t_0) = 0, and p > 0 on T - U. Here is used to represent p(t_i) in the paper. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem16 27356* Lemma for stoweid 27403. The subset of functions in the algebra , with values in [ 0 , 1 ], is closed under multiplication. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem17 27357* This lemma proves that the function (as defined in [BrosowskiDeutsh] p. 91, at the end of page 91) belongs to the subalgebra. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem18 27358* This theorem proves Lemma 2 in [BrosowskiDeutsh] p. 92 when A is empty, the trivial case. Here D is used to denote the set A of Lemma 2, because the variable A is used for the subalgebra. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem19 27359* If a set of real functions is closed under multiplication and it contains constants, then it is closed under finite exponentiation. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem20 27360* If a set A of real functions from a common domain T is closed under the sum of two functions, then it is closed under the sum of a finite number of functions, indexed by G. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem21 27361* Once the Stone Weierstrass theorem has been proven for approximating nonnegative functions, then this lemma is used to extend the result to functions with (possibly) negative values. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem22 27362* If a set of real functions from a common domain is closed under addition, multiplication and it contains constants, then it is closed under subtraction. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem23 27363* This lemma is used to prove the existence of a function pt as in the beginning of Lemma 1 [BrosowskiDeutsh] p. 90: for all t in T - U, there exists a function p in the subalgebra, such that pt ( t0 ) = 0 , pt ( t ) > 0, and 0 <= pt <= 1. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem24 27364* This lemma proves that for sufficiently large, qn( t ) > ( 1 - epsilon ), for all in : see Lemma 1 [BrosowskiDeutsh] p. 90, (at the bottom of page 90). is used to represent qn in the paper, to represent in the paper, to represent , to represent δ, and to represent ε. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem25 27365* This lemma proves that for n sufficiently large, qn( t ) < ε, for all in : see Lemma 1 [BrosowskiDeutsh] p. 91 (at the top of page 91). is used to represent qn in the paper, to represent n in the paper, to represent k, to represent δ, to represent p, and to represent ε. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem26 27366* This lemma is used to prove that there is a function as in the proof of [BrosowskiDeutsh] p. 92: this lemma proves that g(t) > ( j - 4 / 3 ) * ε. Here is used to represnt j in the paper, is used to represent A in the paper, is used to represent t, and is used to represent ε. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem27 27367* This lemma is used to prove the existence of a function p as in Lemma 1 [BrosowskiDeutsh] p. 90: p is in the subalgebra, such that 0 <= p <= 1, p(t_0) = 0, and p > 0 on T - U. Here is used to represent p(t_i) in the paper. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem28 27368* There exists a δ as in Lemma 1 [BrosowskiDeutsh] p. 90: 0 < delta < 1 and p >= delta on . Here is used to represent δ in the paper. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem29 27369* When the hypothesis for the extreme value theorem hold, then the inf of the range of the function belongs to the range, it is real and it a lower bound of the range. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem30 27370* This lemma is used to prove the existence of a function p as in Lemma 1 [BrosowskiDeutsh] p. 90: p is in the subalgebra, such that 0 <= p <= 1, p(t_0) = 0, and p > 0 on T - U. Z is used for t0, P is used for p, is used for p(t_i). (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem31 27371* This lemma is used to prove that there exists a function x as in the proof of Lemma 2 in [BrosowskiDeutsh] p. 91: assuming that is a finite subset of , indexes a finite set of functions in the subalgebra (of the Stone Weierstrass theorem), such that for all ranging in the finite indexing set, 0 ≤ xi ≤ 1, xi < ε / m on V(ti), and xi > 1 - ε / m on . Here M is used to represent m in the paper, is used to represent ε in the paper, vi is used to represent V(ti). (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem32 27372* If a set A of real functions from a common domain T is a subalgebra and it contains constants, then it is closed under the sum of a finite number of functions, indexed by G and finally scaled by a real Y. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem33 27373* If a set of real functions from a common domain is closed under addition, multiplication and it contains constants, then it is closed under subtraction. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem34 27374* This lemma proves that for all in there is a as in the proof of [BrosowskiDeutsh] p. 91 (at the bottom of page 91 and at the top of page 92): (j-4/3) * ε < f(t) <= (j-1/3) * ε , g(t) < (j+1/3) * ε, and g(t) > (j-4/3) * ε. Here is used to represent ε in the paper. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem35 27375* This lemma is used to prove the existence of a function p as in Lemma 1 of [BrosowskiDeutsh] p. 90: p is in the subalgebra, such that 0 <= p <= 1, p(t_0) = 0, and p > 0 on T - U. Here is used to represent p(t_i) in the paper. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem36 27376* This lemma is used to prove the existence of a function pt as in Lemma 1 of [BrosowskiDeutsh] p. 90 (at the beginning of Lemma 1): for all t in T - U, there exists a function p in the subalgebra, such that pt ( t0 ) = 0 , pt ( t ) > 0, and 0 <= pt <= 1. Z is used for t0 , S is used for t e. T - U , h is used for pt . G is used for (ht)^2 and the final h is a normalized version of G ( divided by its norm, see the variable N ). (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem37 27377* This lemma is used to prove the existence of a function p as in Lemma 1 of [BrosowskiDeutsh] p. 90: p is in the subalgebra, such that 0 <= p <= 1, p(t_0) = 0, and p > 0 on T - U. Z is used for t0, P is used for p, is used for p(t_i). (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem38 27378* This lemma is used to prove the existence of a function p as in Lemma 1 of [BrosowskiDeutsh] p. 90: p is in the subalgebra, such that 0 <= p <= 1, p(t_0) = 0, and p > 0 on T - U. Z is used for t0, P is used for p, is used for p(t_i). (Contributed by GlaucoSiliprandi, 20-Apr-2017.)

Theoremstoweidlem39 27379* This lemma is used to prove that there exists a function x as in the proof of Lemma 2 in [BrosowskiDeutsh] p. 91: assuming that is a finite subset of , indexes a finite set of functions in the subalgebra (of the Stone Weierstrass theorem), such that for all i ranging in the finite indexing set, 0 ≤ xi ≤ 1, xi < ε / m on V(ti), and xi > 1 - ε / m on . Here is used to represent A in the paper's Lemma 2 (because is used for the subalgebra), is used to represent m in the paper, is used to represent ε, and vi is used to represent V(ti). is just a local definition, used to shorten statements. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem40 27380* This lemma proves that qn is in the subalgebra, as in the proof of Lemma 1 in [BrosowskiDeutsh] p. 90. Q is used to represent qn in the paper, N is used to represent n in the paper, and M is used to represent k^n in the paper. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem41 27381* This lemma is used to prove that there exists x as in Lemma 1 of [BrosowskiDeutsh] p. 90: 0 <= x(t) <= 1 for all t in T, x(t) < epsilon for all t in V, x(t) > 1 - epsilon for all t in T \ U. Here we prove the very last step of the proof of Lemma 1: "The result follows from taking x = 1 - qn";. Here is used to represent ε in the paper, and to represent qn in the paper. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem42 27382* This lemma is used to prove that built as in Lemma 2 of [BrosowskiDeutsh] p. 91, is such that x > 1 - ε on B. Here is used to represent in the paper, and E is used to represent ε in the paper. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem43 27383* This lemma is used to prove the existence of a function pt as in Lemma 1 of [BrosowskiDeutsh] p. 90 (at the beginning of Lemma 1): for all t in T - U, there exists a function pt in the subalgebra, such that pt( t0 ) = 0 , pt ( t ) > 0, and 0 <= pt <= 1. Hera Z is used for t0 , S is used for t e. T - U , h is used for pt. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem44 27384* This lemma is used to prove the existence of a function p as in Lemma 1 of [BrosowskiDeutsh] p. 90: p is in the subalgebra, such that 0 <= p <= 1, p(t_0) = 0, and p > 0 on T - U. Z is used to represent t0 in the paper. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem45 27385* This lemma proves that, given an appropriate (in another theorem we prove such a exists), there exists a function qn as in the proof of Lemma 1 in [BrosowskiDeutsh] p. 91 ( at the top of page 91): 0 <= qn <= 1 , qn < ε on T \ U, and qn > 1 - ε on . We use y to represent the final qn in the paper (the one with n large enough), to represent in the paper, to represent , to represent δ, to represent ε, and to represent . (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem46 27386* This lemma proves that sets U(t) as defined in Lemma 1 of [BrosowskiDeutsh] p. 90, are a cover of T \ U. Using this lemma, in a later theorem we will prove that a finite subcover exists. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem47 27387* Subtracting a constant from a real continuous function gives another continuous function. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem48 27388* This lemma is used to prove that built as in Lemma 2 of [BrosowskiDeutsh] p. 91, is such that x < ε on . Here is used to represent in the paper, is used to represent ε in the paper, and is used to represent in the paper (because is always used to represent the subalgebra). (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem49 27389* There exists a function qn as in the proof of Lemma 1 in [BrosowskiDeutsh] p. 91 (at the top of page 91): 0 <= qn <= 1 , qn < ε on , and qn > 1 - ε on . Here y is used to represent the final qn in the paper (the one with n large enough), represents in the paper, represents , represents δ, represents ε, and represents . (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem50 27390* This lemma proves that sets U(t) as defined in Lemma 1 of [BrosowskiDeutsh] p. 90, contain a finite subcover of T \ U. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem51 27391* There exists a function x as in the proof of Lemma 2 in [BrosowskiDeutsh] p. 91. Here is used to represent in the paper, because here is used for the subalgebra of functions. is used to represent ε in the paper. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem52 27392* There exists a neighborood V as in Lemma 1 of [BrosowskiDeutsh] p. 90. Here Z is used to represent t0 in the paper, and v is used to represent V in the paper. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem53 27393* This lemma is used to prove the existence of a function p as in Lemma 1 of [BrosowskiDeutsh] p. 90: p is in the subalgebra, such that 0 <= p <= 1, p(t_0) = 0, and p > 0 on T - U. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem54 27394* There exists a function as in the proof of Lemma 2 in [BrosowskiDeutsh] p. 91. Here is used to represent in the paper, because here is used for the subalgebra of functions. is used to represent ε in the paper. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem55 27395* This lemma proves the existence of a function p as in the proof of Lemma 1 in [BrosowskiDeutsh] p. 90: p is in the subalgebra, such that 0 <= p <= 1, p(t_0) = 0, and p > 0 on T - U. Here Z is used to represent t0 in the paper. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem56 27396* This theorem proves Lemma 1 in [BrosowskiDeutsh] p. 90. Here is used to represent t0 in the paper, is used to represent in the paper, and is used to represent ε (Contributed by Glauco Siliprandi, 20-Apr-2017.)

Theoremstoweidlem57 27397* There exists a function x as in the proof of Lemma 2 in [BrosowskiDeutsh] p. 91. In this theorem, it is proven the non-trivial case (the closed set D is nonempty). Here D is used to represent A in the paper, because the variable A is used for the subalgebra of functions. (Contributed by Glauco Siliprandi, 20-Apr-2017.)