Recent content by tomboi03

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    Max Speed of a Porsche 944 Turbo - 113317.4 W

    nvm i got it! hahaha ;) thanks!
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    Max Speed of a Porsche 944 Turbo - 113317.4 W

    okay uh... the thing is... I know P=F*v right? so, if P= 113317.4 and F= 9996 i get v= 11.336 m/s... and that is not nearly enough for a porsche to reach it's max speed... it's like the min speed if anything.
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    Max Speed of a Porsche 944 Turbo - 113317.4 W

    A Porsche 944 Turbo has a rated engine power of 217 hp. 30% of the power is lost in the drive train, and 70% reaches the wheels. The total mass of the car and driver is 1530 kg, and two-thirds of the weight is over the drive wheels. okay... sooo... I know that P = F(car)*velocity =...
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    Topological Groups to Properties and Solutions

    If A and B are subsets of G, let A*B denote the set of all points a*b for a in A and b in B. Let A^(-1) denote the set of all points a^(-1), for a in A. a)A neighborhood V of the identity element e is said to be symmetric if V = V^(-1) . If U is a neighborhood of e, show there is a...
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    Normal subgroup; topological group

    The integers Z are a normal subgroup of (R,+). The quotient R/Z is a familiar topological group; what is it? okay... i attempted this problem... and I don't know if i did it right... but can you guys check it? Thanks~ R/Z is a familiar topological group and Z are a normal subgroup of...
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    Show H & \bar{H} Topological Groups if H Subgroup of G

    Let H be a subspace of G. Show that if H is also a subgroup of G, then both H and\bar{H} are topological groups. So, this is what I've got... if H is a subgroup of G then H \subset G. Since H is a subspace of G then H is an open subset. But, i don't even know if that's right. How...
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    Clarifying Topology Basics: What is U?

    It helps but... Can i ask when U is used for the whole set? Because doesn't the subject topology use U as the whole set?
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    Clarifying Topology Basics: What is U?

    This is a very simple question... Because I'm not very good at these... notations... I feel like I need a clarification on what this means.. if X is a set, a basis for a topology on X is a collection B of subsets of X (called basis elements) satisfying the following properties. 1. For...
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    Convergence of fn: R->R to f: R->R

    Let fn : R \rightarrow R be the function fn= \frac{1}{n^3 [x-(1/n)]^2+1} Let f : R \rightarrow R be the zero function. a. Show that fn(x) \rightarrow f(x) for each x \in R b. Show that fn does not converge uniformly to f. (This shows that the converse of Theorem 21.6 does not hold; the...
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    Show Uniform Convergence of Sequence of Functions on Set X

    Let X be a set, and let fn : X \rightarrow R be a sequence of functions. Let p be the uniform metric on the space Rx. Show that the sequence (fn) converges uniformly to the function f : X \rightarrow R if and only if the sequence (fn) converges to f as elements of the metric space (RX, p)...
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    Is the Function F(x, y) Continuous at All Points?

    Let F: R x R -> R be defined by the equation F(x x y) = { xy/(x^2 + y^2) if x x y \neq 0 x 0 ; 0 if x x y = 0 x 0 a. Show that F is continuous in each variable separately. b. Compute the function g: R-> R defined by g(x) = F(x x x) c. Show that F is not continuous. I know how to do...
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    Proving Topology Continuity for F: X x Y -> Z in Separate Variables

    Let F: X x Y -> Z. We say that F is continuous in each variable separately if for each y0 in Y, the map h: X-> Z defined by h(X)= F( x x y0) is continuous, and for each x0 in X, the map k: Y-> Z defined by k(y) =F(x0 x y) is continuous. Show that if F is continuous, then F is continuous in...
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    Embeddings of X in Y and Y in X Defined by f(x) and g(y)

    x0 \inX and y0\inY, f:X\rightarrowX x Y and g: Y\rightarrowX x Y defined by f(x)= x x y0 and g(y)=x0 x y are embeddings This is all I have... f(x): {(x,y): x\inX and y\inY} g(y): {(x,y): x\inX and y\inY} right? soo... embeddings are... one instance of some mathematical structure contained...
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    I: X'->X the identity function with topology

    Let X and X' denote a single set in the two topologies T and T', respectively. Let i:X'-> X be the identity function a. Show that i is continuous <=> T' is finer than T. b. Show that i is a homeomorphism <=> T'=T This is all I've got. According to the first statement... X \subset T and...
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    Is the Closure of a Subset Always in the Union of Neighborhoods?

    Let A, B, and A\alpha denote subsets of a space X. neighborhood of \bigcupA\alpha \supset \bigcup neighborhood of A\alpha; give an example where equality fails.Criticize the following "proof" of the above statement: if {A\alpha} is a collection of sets in X and if x \in neighborhood of...
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