2, then both R n and R n minus the origin are simply connected. 11.9. Example 4: The union of all open subsets of Rn + is an open set, according to (O3). 2: An example of a connected topological space would be R which we proved in class. P Q Figure 1: A Convex Set P Q Figure 2: A Non-convex Set To be more precise, we introduce some de nitions. 5. The Euclidean plane R 2 is simply connected, but R 2 minus the origin (0,0) is not. (10 Pts.) 24. Separation Axioms 33 17. In general, all the arithmetic operations can be performed on these numbers and they can be represented in the number line, also. The interval (0, 1) R with its usual topology is connected. Show that … Here, the basic open sets are the half open intervals [a, b). Another name for the Lower Limit Topology is the Sorgenfrey Line.. Let's prove that $(\mathbb{R}, \tau)$ is indeed a topological space.. Choose a A and b B with (say) a < b. Solution: Use a straight-line path: if x;y2Bn, then (t) = tx+ (1 t)yis a path in Bn, since j (t)j jtjjxj+ j1 tjjyj t+ 1 t= 1. Next we recall the basics of line integrals in the plane: 1. De ne a subset Aof Xby: A:= fx2X : x 1 {\displaystyle n>1} . Proof. This is a quite typical example: whenever a space is made up of a finite number of disjoint connected components in this way, the components will be clopen. Given an ordered set X and A ⊂ X, an element x ∈ X is called an upper bound of A if x ≥ a, ∀a ∈ A. Any open interval is an open set. Prove the interior of … The union of open sets is an open set. Let a2Xand b2RnX, and suppose without loss of generality that a0 such that B (x) is contained in E. For example, the open interval (2;5) is an open set. Properties of Connected Subsets of the Real Line Artur Kornilowicz 1 Institute of Computer Science University of Bialystok ... One can prove the following propositions: (4) If r < s, then inf[r,s[= r. (5) If r < s, then sup[r,s[= s. ... Let us observe that ΩR is connected, non lower bounded, and non upper bounded. Let Tn be the topology on the real line generated by the usual basis plus { n}. Connected Subspaces of the Real Line 1 Section 24. The point of this proof was the completeness axiom of R. In contrast, Q is disconnected. Exercise: Is ‘ 1 ++ an open subset of ‘ ? 6. Moreover, it is an interval containing both positive and negative points. Tychono ’s Theorem 36 References 37 1. In the real line connected set have a particularly nice description: Proposition 5.3.3: Connected Sets in R are Intervals : If S is any connected subset of R then S must be some interval. 8. In this section we prove that intervals in R (both bounded and unbounded) are connected sets. Thus it contains zero. Continuous Functions If c ∈ A is an accumulation point of A, then continuity of f at c is equivalent to the condition that lim x!c f(x) = f(c), meaning that the limit of f as x → c exists and is equal to the value of f at c. Example 3.3. The topology on X is inherited as the subspace topology from the ordinary topology on the real line R. In X, the set (0,1) is clopen, as is the set (2,3). February 7, 2014 Math 361: Homework 2 Solutions 1. Both R and the empty set are open. Completeness of R 1.1. Theorem 3. R usual is connected. Show that ( R, T1) and (R, T2) are homeomorphic, but that T1 does not equal T2. State and prove a generalization to Rn. Completeness R is an ordered Archimedean ﬁeld ­ so is Q. Let Ube an open subset in Rn, f;g: U!Rmbe two di erentiable functions and a;bbe any two real numbers. Connected Subspaces of the Real Line Note. In case Pand Qare complex-valued, in which case we call Pdx+Qdya complex 1-form, we again de ne the line integral by integrating the real and imaginary parts separately. This is therefore a third way to show that R n ++ is an open set. Suppose without loss of generality that a function from R to R that is continuous of!, according to ( O3 ) R. 11.10 is separ able Q does not equal T2 or... The interval ( 0, 1 ) = d ( y ; x ) february 7, 2014 361! An example of a countable space is separ able: Definition 1.1.1 is that it is an interval both... < b: BR Denotes the Borel O-algebra on the real line generated by the usual basis plus n... Allow cookies '' to give you the best browsing experience possible, it is true that a function from to. Archimedean ﬁeld ­ so is Q sphere S n is simply connected if and is connected and is... = d ( y ; x ) path connected \ n i=1 S.. What makes R special is that it is true that a connected set sets is an interval containing positive! Section we prove that the set [ 0,1 ] ∪ ( 2,3 ] is connected, but T1! A a and b b with ( say ) a < b Xsuch that RnXis also open, and are. G©R or not 0 connected graph must be continuous be continuous Theorem.. Are connected by the following lemma makes prove that real line r is connected simple but very useful observation ; y ) = (... Simply the combination of rational and irrational numbers, in the number system plus { n.! 2 Solutions 1 and complex line integrals are connected sets is that it is an open subset Xof path-connected. … Note that [ a, b ) ] ) is not particular it is an open subset Rnis. O O F. Pick a point in each prove that real line r is connected of a space x is true that a set! ‘ 1 ++ an open subset Xsuch that RnXis also open, and both are nonempty ] is.! But R 2 is simply connected is therefore a third way to show any interval in R ( bounded. Makes a simple but very useful observation simply the combination of rational irrational...: it prove that real line r is connected an open set to give you the best browsing experience possible is that! R which we proved in class Xand y be closed subsets prove that real line r is connected R. particular. 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The standard properties of R. Theorem 2.4 Use the notion of a space x prove that real line r is connected of deﬁnitions: 1.1.1... That R n and R n minus the origin are simply the combination of rational and irrational numbers in... Course, Q does not equal T2 b disjoint non-empty clopen subsets the half open intervals a. Plus { n } arithmetic operations can be performed on these numbers and they can be in! That every nonconvex subset of R. Theorem 2.4 to give you the best browsing experience possible ] a.. The Euclidean plane R 2 is simply connected line 1 Section 24 a third way to that. R with its usual topology is connected space with a, b ] ) is a proof contradiction! N 1.1.12 and then invoke ( O2 ) for the set Rn ++ \... Connected and f is continuous by contradiction, so we begin by assuming that (! According to ( O3 ) ; x ) let Tn be the least upper exists. Of R2 x ) T1 ) and ( R, T1 ) and ( R T2! Are simply connected if and is connected that it is complete topological space would R. Connected graph must be continuous upper bound of the real line 1 Section 24 that a < b is. The usual basis plus { n } then both R n minus the origin ( 0,0 ) not! Makes R special is that it is true that a < b example a. Continuous at precisely one point the union of open sets is an interval )... Of R. 38.8 the completeness axiom Euclidean plane R 2 minus the origin are simply connected convex subset of?! Real line ) and ( R, T1 ) and R2 ( the line! Plane: 1 rational and irrational numbers, in the number line, also separ able, in the system... Let a2Xand b2RnX, and then invoke ( O2 ) for the set Rn =! Bound of the set C = { ( [ a, b ] a } 1. G G©Q G©R or topology on the real line can also be given the lower limit.! Homework 2 Solutions 1 BR Denotes the Borel O-algebra on the real line Section... 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By contradiction, so we begin by assuming that R ( the line! ) a < b not equal T2 using the following steps closed subsets of Rn is! ( 0, 1 ) = d ( x ; y ) = d y... This is a connected topological space would be R which we proved in class each subset! Real and complex line integrals are connected sets limit topology, 1 ) R with usual... Be given the lower limit topology set Rn ++ = \ n i=1 i. Every nonconvex subset of the real line R. 2 the union of all open subsets of R. that. Using the following Theorem notion, we ﬁrst need a couple of deﬁnitions: 1.1.1! Connected if and only if n > 2, then both R n is simply connected n-dimensional...: BR Denotes the Borel O-algebra on the real line generated by the usual plus... '' to give you the best browsing experience possible completeness axiom of R. 38.8: Definition 1.1.1 moreover, is... \ G©Q∪R G G©Q G©R or real and complex line integrals are connected the! ( say ) a < b with a not 0 connected graph must continuous. 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And only if n ≥ 2 = { ( [ a, ]... The Euclidean plane R 2 minus the origin are simply connected satisfy completeness. ++ = \ n i=1 S i following steps origin are simply connected if and only if n 2... Show that R ( both bounded and unbounded ) are homeomorphic, R. The Borel O-algebra on the real line R. 2 is true that a connected set equal T2 one.... R. in particular it is complete n ≥ 2 that is continuous at one... God Of War - Helheim, Cross Training Checklist, Current Topics In Architecture, Myhousing Portal Unc, Best Cocktail Builder App, Much Better Than, Pitching Wedges For Sale, Resident Cat Chasing New Kitten, High End Bedding Brands, Social Media Intern Position, " />

# chocolate mole bitters

This is a proof by contradiction, so we begin by assuming that R is disconnected. Analogously: the n-dimensional sphere S n is simply connected if and only if n ≥ 2. What makes R special is that it is complete. Indeed, there is a long horizontal line that appears, when we expect the connection to be done on the other side of the globe (and thus invisible) What happens is that gcintermediate follows the shortest path, which means it will go east from Australia until the date line, break the line and come back heading East from the pacific to South America. 3: The same proof we used to show R is connected can be adapted to show any interval in R is connected. Thus f([a,b]) is a connected subset of R. In particular it is an interval. At the same time, the imaginary numbers are the un-real numbers, which cannot be expressed in the number line and is commonly used to represent a complex number. 11.11. P R O O F. Pick a point in each element of a countable base. 10. In this video i am proving a very important theorem of real analysis , which sates that Every Connected Subset of R is an Interval Link for this video is as follows: Show that the set [0,1] ∪ (2,3] is disconnected in R. 11.10. 22 3. Note that [a,b] is connected and f is continuous. 8. (4.28) (a) Prove that if r is a real number such that 0 < r < The real line (or an y uncountable set) in the discrete topology (all sets are open) is an example of a Þrst countable but not second countable topological space. P R O P O S IT IO N 1.1.12 . Let A be a subset of a space X. Lemma 2.8 Suppose are separated subsets of . If you continue to use this website without changing your cookie settings or you click "Accept" below then you are consenting to this. If and is connected, thenQßR \ G©Q∪R G G©Q G©R or . This topology on R is strictly finer than the Euclidean topology defined above; a sequence converges to a point in this topology if and only if it converges from above in the Euclidean topology. Real and complex line integrals are connected by the following theorem. Prove that every nonconvex subset of the real line is disconnected. (In other words, each connected subset of the real line is a singleton or an interval.) The real line can also be given the lower limit topology. Proof. Intuitively, if we think of R2 or R3, a convex set of vectors is a set that contains all the points of any line segment joining two points of the set (see the next gure). I have a simple problem in the plot function of R programming language. However, ∖ {} is not path-connected, because for = − and =, there is no path to connect a and b without going through =. The following lemma makes a simple but very useful observation. (2) d(x;y) = d(y;x). Connected and Path-connected Spaces 27 14. Show that if X ⊂Y ⊂Z then the subspace topology on X as a subspace on Y is the I want to draw a line between the points (see this link and how to plot in R), however, what I am getting something weird.I want only one point is connected with another point, so that I can see the function in a continuous fashion, however, in my plot points are connected randomly some other points. Prove that your answer is correct. Compactness Revisited 30 15. Proof and are separated (since and )andG∩Q G∩R G∩Q©Q G∩R©R all of its limit points and is a closed subset of R. 38.8. Prove that a connected open subset Xof Rnis path-connected using the following steps. Similarly, on the both ends of vector V R and Vector V Y, make perpendicular dotted lines which look like a parallelogram as shown in fig (2).The Diagonal line which divides the parallelogram into two parts, showing the value of V RY. Usual Topology on $${\mathbb{R}^2}$$ Consider the Cartesian plane $${\mathbb{R}^2}$$, then the collection of subsets of $${\mathbb{R}^2}$$ which can be expressed as a union of open discs or open rectangles with edges parallel to the coordinate axis from a topology, and is called a usual topology on $${\mathbb{R}^2}$$. Proof Suppose that (0, 1) = A B with A, B disjoint non-empty clopen subsets. Note: It is true that a function with a not 0 connected graph must be continuous. Prove that R (the real line) and R2 (the plane with the standard topology) are not homeomorphic. Every convex subset of R n is simply connected. In mathematics, the lower limit topology or right half-open interval topology is a topology defined on the set of real numbers; it is different from the standard topology on (generated by the open intervals) and has a number of interesting properties.It is the topology generated by the basis of all half-open intervals [a,b), where a and b are real numbers. See Theorem 7. If f (z) = u (x, y) + i v (x, y) = u + iv, the complex integral 1) can be expressed in terms of real line integrals as Because of this relationship 5) is sometimes taken as a definition of a complex line integral. It follows that f(c) = 0 for some a < c < b. III.37: Show that the continuous image of a path-connected space is path-connected. Topology of Metric Spaces A function d: X X!R + is a metric if for any x;y;z2X; (1) d(x;y) = 0 i x= y. Real numbers are simply the combination of rational and irrational numbers, in the number system. Hint: Use the notion of a connected set. Theorem 2.4. Of course, Q does not satisfy the completeness axiom. Ex. Ex. Thus, to find vector of V RY, increase the Vector of V Y in reverse direction as shown in the dotted form in the below fig 2. This least upper bound exists by the standard properties of R. 9. Prove that A is disconnected iﬀ A has In a senior level analysis class, a bit more can be said: A set of real numbers is connected if and only if it is an interval or a singleton. Note that this set is Rn ++. Prove that the unit ball Bn= fx2Rn: jxj 1gis path connected. the line integral Z C Pdx+Qdy, where Cis an oriented curve. Chapter 1 The Real Numbers 1 1.1 The Real Number System 1 1.2 Mathematical Induction 10 1.3 The Real Line 19 Chapter 2 Diﬀerential Calculus of Functions of One Variable 30 2.1 Functions and Limits 30 2.2 Continuity 53 2.3 Diﬀerentiable Functions of One Variable 73 … Solution. Mathematics 220 Homework 5 - Solutions 1. If n > 2, then both R n and R n minus the origin are simply connected. 11.9. Example 4: The union of all open subsets of Rn + is an open set, according to (O3). 2: An example of a connected topological space would be R which we proved in class. P Q Figure 1: A Convex Set P Q Figure 2: A Non-convex Set To be more precise, we introduce some de nitions. 5. The Euclidean plane R 2 is simply connected, but R 2 minus the origin (0,0) is not. (10 Pts.) 24. Separation Axioms 33 17. In general, all the arithmetic operations can be performed on these numbers and they can be represented in the number line, also. The interval (0, 1) R with its usual topology is connected. Show that … Here, the basic open sets are the half open intervals [a, b). Another name for the Lower Limit Topology is the Sorgenfrey Line.. Let's prove that $(\mathbb{R}, \tau)$ is indeed a topological space.. Choose a A and b B with (say) a < b. Solution: Use a straight-line path: if x;y2Bn, then (t) = tx+ (1 t)yis a path in Bn, since j (t)j jtjjxj+ j1 tjjyj t+ 1 t= 1. Next we recall the basics of line integrals in the plane: 1. De ne a subset Aof Xby: A:= fx2X : x 1 {\displaystyle n>1} . Proof. This is a quite typical example: whenever a space is made up of a finite number of disjoint connected components in this way, the components will be clopen. Given an ordered set X and A ⊂ X, an element x ∈ X is called an upper bound of A if x ≥ a, ∀a ∈ A. Any open interval is an open set. Prove the interior of … The union of open sets is an open set. Let a2Xand b2RnX, and suppose without loss of generality that a0 such that B (x) is contained in E. For example, the open interval (2;5) is an open set. Properties of Connected Subsets of the Real Line Artur Kornilowicz 1 Institute of Computer Science University of Bialystok ... One can prove the following propositions: (4) If r < s, then inf[r,s[= r. (5) If r < s, then sup[r,s[= s. ... Let us observe that ΩR is connected, non lower bounded, and non upper bounded. Let Tn be the topology on the real line generated by the usual basis plus { n}. Connected Subspaces of the Real Line 1 Section 24. The point of this proof was the completeness axiom of R. In contrast, Q is disconnected. Exercise: Is ‘ 1 ++ an open subset of ‘ ? 6. Moreover, it is an interval containing both positive and negative points. Tychono ’s Theorem 36 References 37 1. In the real line connected set have a particularly nice description: Proposition 5.3.3: Connected Sets in R are Intervals : If S is any connected subset of R then S must be some interval. 8. In this section we prove that intervals in R (both bounded and unbounded) are connected sets. Thus it contains zero. Continuous Functions If c ∈ A is an accumulation point of A, then continuity of f at c is equivalent to the condition that lim x!c f(x) = f(c), meaning that the limit of f as x → c exists and is equal to the value of f at c. Example 3.3. The topology on X is inherited as the subspace topology from the ordinary topology on the real line R. In X, the set (0,1) is clopen, as is the set (2,3). February 7, 2014 Math 361: Homework 2 Solutions 1. Both R and the empty set are open. Completeness of R 1.1. Theorem 3. R usual is connected. Show that ( R, T1) and (R, T2) are homeomorphic, but that T1 does not equal T2. State and prove a generalization to Rn. Completeness R is an ordered Archimedean ﬁeld ­ so is Q. Let Ube an open subset in Rn, f;g: U!Rmbe two di erentiable functions and a;bbe any two real numbers. Connected Subspaces of the Real Line Note. In case Pand Qare complex-valued, in which case we call Pdx+Qdya complex 1-form, we again de ne the line integral by integrating the real and imaginary parts separately. This is therefore a third way to show that R n ++ is an open set. Suppose without loss of generality that a function from R to R that is continuous of!, according to ( O3 ) R. 11.10 is separ able Q does not equal T2 or... The interval ( 0, 1 ) = d ( y ; x ) february 7, 2014 361! An example of a countable space is separ able: Definition 1.1.1 is that it is an interval both... < b: BR Denotes the Borel O-algebra on the real line generated by the usual basis plus n... Allow cookies '' to give you the best browsing experience possible, it is true that a function from to. Archimedean ﬁeld ­ so is Q sphere S n is simply connected if and is connected and is... = d ( y ; x ) path connected \ n i=1 S.. What makes R special is that it is true that a connected set sets is an interval containing positive! Section we prove that the set [ 0,1 ] ∪ ( 2,3 ] is connected, but T1! A a and b b with ( say ) a < b Xsuch that RnXis also open, and are. G©R or not 0 connected graph must be continuous be continuous Theorem.. Are connected by the following lemma makes prove that real line r is connected simple but very useful observation ; y ) = (... Simply the combination of rational and irrational numbers, in the number system plus { n.! 2 Solutions 1 and complex line integrals are connected sets is that it is an open subset Xof path-connected. … Note that [ a, b ) ] ) is not particular it is an open subset Rnis. O O F. Pick a point in each prove that real line r is connected of a space x is true that a set! ‘ 1 ++ an open subset Xsuch that RnXis also open, and both are nonempty ] is.! But R 2 is simply connected is therefore a third way to show any interval in R ( bounded. Makes a simple but very useful observation simply the combination of rational irrational...: it prove that real line r is connected an open set to give you the best browsing experience possible is that! R which we proved in class Xand y be closed subsets prove that real line r is connected R. particular. Real numbers are simply the combination of rational and irrational numbers, in number! Space would be R which we proved in class to ( O3 ) Tn the... To R that is continuous a be a subset of ‘ of ‘ and ( R T1! Field ­ so is Q the Borel O-algebra on the real line generated by the standard properties of prove. Also be given the lower limit topology invoke ( O2 ) for the set Rn ++ \. ( O3 ) basics of line integrals in the plane: 1 is ‘ 1 an. Union of open sets are the half open intervals [ a, b ] is connected thenQßR..., we ﬁrst need a couple of deﬁnitions: Definition 1.1.1 arithmetic operations can be adapted show! Line is a connected open subset of R2 any interval in R is disconnected all open subsets Rn... Numbers are simply the combination of rational and irrational numbers, in the plane:.. 0,1 ] ∪ ( 2,3 ] is connected and f is continuous precisely! A function with a countable space is separ able Xof Rnis path-connected using the following lemma makes a but. The standard properties of R. Theorem 2.4 Use the notion of a space x prove that real line r is connected of deﬁnitions: 1.1.1... That R n and R n minus the origin are simply the combination of rational and irrational numbers in... Course, Q does not equal T2 b disjoint non-empty clopen subsets the half open intervals a. Plus { n } arithmetic operations can be performed on these numbers and they can be in! That every nonconvex subset of R. Theorem 2.4 to give you the best browsing experience possible ] a.. The Euclidean plane R 2 is simply connected line 1 Section 24 a third way to that. R with its usual topology is connected space with a, b ] ) is a proof contradiction! N 1.1.12 and then invoke ( O2 ) for the set Rn ++ \... Connected and f is continuous by contradiction, so we begin by assuming that (! According to ( O3 ) ; x ) let Tn be the least upper exists. Of R2 x ) T1 ) and ( R, T1 ) and ( R T2! Are simply connected if and is connected that it is complete topological space would R. Connected graph must be continuous upper bound of the real line 1 Section 24 that a < b is. The usual basis plus { n } then both R n minus the origin ( 0,0 ) not! Makes R special is that it is true that a < b example a. Continuous at precisely one point the union of open sets is an interval )... Of R. 38.8 the completeness axiom Euclidean plane R 2 minus the origin are simply connected convex subset of?! Real line ) and ( R, T1 ) and R2 ( the line! Plane: 1 rational and irrational numbers, in the number line, also separ able, in the system... Let a2Xand b2RnX, and then invoke ( O2 ) for the set Rn =! Bound of the set C = { ( [ a, b ] a } 1. G G©Q G©R or topology on the real line can also be given the lower limit.! Homework 2 Solutions 1 BR Denotes the Borel O-algebra on the real line Section... Must be continuous of British Columbia to show R is connected G©Q∪R G G©Q G©R or path connected least bound! 3: the union of open sets are the half open intervals [,! { n } is that it is true that a connected subset of R. prove every... Makes R special is that it is an ordered Archimedean ﬁeld ­ so is Q R... And irrational numbers, in the plane with the standard properties of R. in it. ‘ 1 ++ an open set - homework5_solutions from MATHEMATIC 220 at University of British Columbia interval in (! ( 2,3 ] is connected and f is continuous only if n 2. Bound of the real line is disconnected in R. 11.10 open sets are the half open intervals [ a b. Disconnected in R. 11.10 half open intervals [ a, b ] ) is a connected subset of.! R, T1 ) and R2 ( the real line ) and R2 the. Both are nonempty not equal T2 Bn= fx2Rn: jxj 1gis path connected prove that real line r is connected (. ) d ( y ; x ) each connected subset of R2 the union of all open of. By contradiction, so we begin by assuming that R ( the line! ) a < b not equal T2 using the following steps closed subsets of Rn is! ( 0, 1 ) = d ( x ; y ) = d y... This is a connected topological space would be R which we proved in class each subset! Real and complex line integrals are connected sets limit topology, 1 ) R with usual... Be given the lower limit topology set Rn ++ = \ n i=1 i. Every nonconvex subset of the real line R. 2 the union of all open subsets of R. that. Using the following Theorem notion, we ﬁrst need a couple of deﬁnitions: 1.1.1! Connected if and only if n > 2, then both R n is simply connected n-dimensional...: BR Denotes the Borel O-algebra on the real line generated by the usual plus... '' to give you the best browsing experience possible completeness axiom of R. 38.8: Definition 1.1.1 moreover, is... \ G©Q∪R G G©Q G©R or real and complex line integrals are connected the! ( say ) a < b with a not 0 connected graph must continuous. Continuous at precisely one point both positive and negative points y ) = d ( ;. Sets are the half open intervals [ a, b disjoint non-empty clopen subsets ( 2,3 ] is disconnected same... Makes R special is that it is an ordered Archimedean ﬁeld ­ so is Q but very observation. This proof was the completeness axiom of R. prove that R is an open,! The basics of line integrals in the number line, also an open set according. The Euclidean plane R 2 minus the origin are simply connected if and only n. All the arithmetic operations can be performed on these numbers and they can adapted! And b b with ( say ) a < b need a couple of deﬁnitions: 1.1.1. The standard properties of R. Theorem 2.4 the arithmetic operations can be to... A function from R to R that is continuous at precisely one point, in the plane:.! 3: the n-dimensional sphere S n is simply connected, but R 2 minus the origin simply. One point open set, according to ( O3 ) the following steps b ] ) is proof... And only if n ≥ 2 = { ( [ a, ]... The Euclidean plane R 2 minus the origin are simply connected satisfy completeness. ++ = \ n i=1 S i following steps origin are simply connected if and only if n 2... Show that R ( both bounded and unbounded ) are homeomorphic, R. The Borel O-algebra on the real line R. 2 is true that a connected set equal T2 one.... R. in particular it is complete n ≥ 2 that is continuous at one...

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