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Differential Geometry

Do non-orthogonal coordinate systems mean dependent coordinates?
4.6K threads
Undergrad Do non-orthogonal coordinate systems mean dependent coordinates?
Undergrad Proving a convergent sequence is bounded
  • cbarker1
  • · Replies 3 ·
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3
Undergrad How Does Fourier Transform Analyze Beats in Signals?
  • Salmone
  • · Replies 7 ·
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7
Undergrad Proof of Induction Principle starting from N, not from 1
  • Hall
  • · Replies 6 ·
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6
Undergrad Looking for an expert on integrals
  • benorin
  • · Replies 0 ·
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0
Discover the Limit of a Sequence with Easy-to-Follow Steps
  • slwarrior64
  • · Replies 2 ·
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2
Graduate Confused by a theorem in Milnor-Stasheff
  • quasar987
  • · Replies 4 ·
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4
How Do Riemann Integrals Handle Function Splits and Summations?
  • evinda
  • · Replies 2 ·
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2
Undergrad Looking for Someone Strong in Analysis
  • benorin
  • · Replies 12 ·
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12
Insights The Extended Riemann Hypothesis and Ramanujan’s Sum
  • fresh_42
  • · Replies 3 ·
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3
Graduate Measure of non-periodicity of almost periodic functions
  • reterty
  • · Replies 1 ·
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1
Recursive Function for Virus Spread: Finding the General Solution
  • Tekilou
  • · Replies 3 ·
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3
Undergrad Hopf Fibration, torus with fibers, do it 2 ways?
  • Spinnor
  • · Replies 14 ·
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14
Proving Lemma 3.3 of L&S: Further Aspects of the Proof
  • Math Amateur
  • · Replies 2 ·
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2
Undergrad What's the definition of "periodic extension of a function"?
  • CGandC
  • · Replies 14 ·
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14
Undergrad Show that (0, ∞) is homeomorphic to (0, 1)
  • Mikaelochi
  • · Replies 6 ·
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6
Undergrad The behavior of a potential-like integral at infinity
  • wrobel
  • · Replies 21 ·
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21
Infinite series involving 'x' has a constant value
  • SatyaDas
  • · Replies 3 ·
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3
Understanding Riemann Integrable Functions: Interpreting D&K Pages 427-428
  • Math Amateur
  • · Replies 2 ·
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2
How can we prove the inequality for the supremum and infimum of f*g and f*g?
  • Math Amateur
  • · Replies 2 ·
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2
Help Needed with Determining B' in Proposition 6.1.2: A Case for n=2
  • Math Amateur
  • · Replies 4 ·
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4
Complex Analysis: Does $\int_{C(0,10)} f(z)$ Equal 0?
  • mathmari
  • · Replies 2 ·
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2
Undergrad In Euclidian space, closed ball is equal to closure of open ball
  • CGandC
  • · Replies 7 ·
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7
Undergrad Duistermaat & Kolk .... Vol II .... Proof of Proposition 6.1.2
  • Math Amateur
  • · Replies 22 ·
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22
Graduate Hausdorff property of projective space
  • Korybut
  • · Replies 9 ·
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9
Graduate Understanding Cantor set C in Ternary form with 1/n factor in front C
  • cbarker1
  • · Replies 4 ·
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4
Undergrad Describing homeomorphisms with the π1 function
  • Mikaelochi
  • · Replies 2 ·
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2
Graduate DMD is better without Ergodic Theory and Koopman Operators
  • AcademicOverAnalysis
  • · Replies 2 ·
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2
Undergrad Simpler Brunnian "rubberband" loops?
  • egmoen
  • · Replies 4 ·
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4
A function given by a logical expression write in the truth table.
  • vokan12
  • · Replies 2 ·
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2
Undergrad Writing down an explicit homotopy
  • Mikaelochi
  • · Replies 4 ·
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4
High School Is there a function for every possible "path"?
  • Jurgen M
  • · Replies 19 ·
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19
Undergrad "Approximating Basis" -- Is there a contemporary term?
  • Ziva
  • · Replies 9 ·
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9
Undergrad Why Does the Complex Conjugate Involve Negating the Argument Theta?
  • Leo Liu
  • · Replies 9 ·
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9
Undergrad Broadly spiralling shape from partial sums of Zeta (0.5 + i t)
  • Swamp Thing
  • · Replies 8 ·
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8
Undergrad Showing that a group acts freely and discretely on real plane
  • kmitza
  • · Replies 5 ·
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5
High School Is the Quotient Topology of Real Numbers Homeomorphic to Real Numbers?
  • Korybut
  • · Replies 6 ·
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6
Undergrad Is this generalization equivalent to usual Aposyndetic
  • kmitza
  • · Replies 2 ·
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2
Graduate Limits and Supremum: Is It True?
  • Mathvsphysics
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3
High School What kind of definition is this?
  • mcastillo356
  • · Replies 23 ·
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23
Does This Sequence Converge Uniformly?
  • mathmari
  • · Replies 4 ·
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4
Complex numbers such that modulus (absolute value) less than or equal to 1.
  • Taleb
  • · Replies 2 ·
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2
High School Why Is the Trick for Open Sets in Quotient Topology Valid?
  • Korybut
  • · Replies 8 ·
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8
Undergrad Doing proofs with the variety function and the Zariski topology
  • Mikaelochi
  • · Replies 5 ·
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5
Undergrad A problem of completeness of a metric space
  • facenian
  • · Replies 3 ·
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3
Undergrad Proving a function f is continuous given A U B = X
  • Mikaelochi
  • · Replies 5 ·
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5
Undergrad Solving Zeno's Paradox: The Flaw in the Notion of Infinity
  • Chris S
  • · Replies 46 ·
2
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46
Undergrad Show R^2 \{(0,0)} and {(x,y) | 1 < sqrt(x^2+y^2) < 3} are homeomorphic
  • Mikaelochi
  • · Replies 8 ·
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8
High School Can we have a complex number in the exponent?
  • docnet
  • · Replies 2 ·
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2
Determine the area, calculate the basis vectors and determine the inner product
  • Karl Karlsson1
  • · Replies 2 ·
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2
Undergrad An open set can be a closed interval?
  • Demystifier
  • · Replies 12 ·
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12
Extrema and convergence of sequence
  • mathmari
  • · Replies 9 ·
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9
Calculate the volume of the set M
  • mathmari
  • · Replies 7 ·
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7
What Percentage Am I Asking For If I Want 60 Million Out of 60 Billion Profit?
  • apw
  • · Replies 2 ·
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2
Need Support? Discover How to Get Help!
  • jaychay
  • · Replies 3 ·
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3
Limit Comparision Test: Get Help Now
  • jaychay
  • · Replies 11 ·
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11
Graduate Topological Data Analysis - Persistent Homology
  • phys_student1
  • · Replies 8 ·
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8
High School Real numbers and complex numbers
  • grzz
  • · Replies 38 ·
2
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38
How to Solve a Harmonic Function Problem Involving Partial Derivatives?
  • jaychay
  • · Replies 3 ·
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3
Cauchy-Riemann Equations test problem
  • jaychay
  • · Replies 6 ·
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6
Understanding the Harmonic Function Problem
  • jaychay
  • · Replies 2 ·
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2
Undergrad Continuity of an inverse of a function
  • archaic
  • · Replies 2 ·
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2
Struggling with Complex Number Function? Need Help?
  • jaychay
  • · Replies 12 ·
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12
Complex number equation graph problem
  • jaychay
  • · Replies 12 ·
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12
Global Extrema of a Trigonometric Function
  • mathmari
  • · Replies 16 ·
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16
No Real Zeroes of $x^6-x^5+x^4-x^3+x^2-x+\dfrac{3}{4}$
  • anemone
  • · Replies 1 ·
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1
Lebesgue Outer Measure .... Carothers, Proposition 16.1 ....
  • Math Amateur
  • · Replies 2 ·
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2
High School What is the nature of dimensionality in 11 dimension M-theory?
  • Paige_Turner
  • · Replies 2 ·
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2
Undergrad Pseudometric Spaces: What Are They and Why Are They Important in Mathematics?
  • Paige_Turner
  • · Replies 9 ·
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9
Graduate Is the Assertion Derived from a General Theorem Trivial or Interesting?
  • wrobel
  • · Replies 0 ·
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0
Finding the Unique Solution of a Polar System with Variable Radius?
  • Jiggerjaw
  • · Replies 2 ·
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2
Undergrad Negative curvature in low dimensions
  • Paige_Turner
  • · Replies 3 ·
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3
Undergrad Is there a "Nice" proof that R^2 is not disconnected when we remove 2 points
  • WWGD
  • · Replies 3 ·
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3
Graduate What Are n-Dimensional Holes in Topology?
  • WWGD
  • · Replies 5 ·
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5
Proving Topology in X: A Look at Union & Intersection
  • mathmari
  • · Replies 2 ·
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2
Undergrad Regarding i^2, and why it's -1 and not 1
  • Grasshopper
  • · Replies 45 ·
2
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45
Undergrad Munkres Chapter 5: Problem involving the Tychonoff Theorem
  • facenian
  • · Replies 7 ·
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7
Graduate How Do You Determine the Mapping Functions in a Curvilinear Coordinate System?
  • zaki
  • · Replies 2 ·
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2
Prove that series converges uniformly
  • fabiancillo
  • · Replies 3 ·
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3
Prove that the algebra generated is dense
  • fabiancillo
  • · Replies 2 ·
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2
Correctness of Statements about Set A in Metric Space X
  • mathmari
  • · Replies 32 ·
2
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32
Graduate Fourier transform of hyperbolic tangent
  • jjr
  • · Replies 6 ·
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6
Prove/Disprove: Uniform Continuity of sin(sin(x))
  • solakis1
  • · Replies 4 ·
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4
F doesn't have in (0,0) a local minimum
  • mathmari
  • · Replies 4 ·
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4
Points of the surface with minimum distance to the point (3,0,0)
  • mathmari
  • · Replies 4 ·
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4
Why is \( T_k \) the Unique Polynomial of Degree \( k \) with These Properties?
  • mathmari
  • · Replies 32 ·
2
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32
F convex iff Hessian matrix positive semidefinite
  • mathmari
  • · Replies 24 ·
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24
What Are Level Lines and Gradients in Multivariable Calculus?
  • mathmari
  • · Replies 22 ·
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22
Is f Differentiable at (0,0)?
  • mathmari
  • · Replies 8 ·
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8
Undergrad Angles between complex vectors
  • Physgeek64
  • · Replies 3 ·
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3
Can the Sum of Two Squares Ever Equal 3 Times a Perfect Square?
  • MathLover_James
  • · Replies 2 ·
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2
Piecewise function: differentiable but not continuously differentiable
  • mathmari
  • · Replies 21 ·
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21
F is partially differentiable in (0,0) but not total differentiable
  • mathmari
  • · Replies 11 ·
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11
Finding the Infimum and Supremum
  • slwarrior64
  • · Replies 4 ·
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4
Undergrad ##(a_n) ## has +10,-10 as partial limits. Then 0 is also a partial limit
  • CGandC
  • · Replies 13 ·
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13
Graduate Is There a Simple Method to Analyze the Boundary of the 3-Sphere?
  • jk22
  • · Replies 43 ·
2
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43
Uniform convergence - Length of graph
  • mathmari
  • · Replies 21 ·
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21
Convergence as for the cofinite topology on R
  • mathmari
  • · Replies 17 ·
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17
Undergrad Is [0,1] under the subspace topology Hausdorff, Compact, or Connected?
  • WWGD
  • · Replies 15 ·
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15
Graduate What Topological Vector Spaces have an uncountable Schauder basis?
  • lugita15
  • · Replies 6 ·
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6
Understanding Example from Topics in Banach Space Integration
  • Sara jj
  • · Replies 2 ·
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2