Famous Question - Badge - Mathematics Stack Exchange

Famous Question

Question with 10,000 views. This badge can be awarded multiple times.

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Find the constant *c* so that p(x) satisfies the condition of being a pmf of one random variable X.

Awarded 1 hour ago

user485656

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Every $R$-module is free $\implies$ $R$ is a division ring

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Leo

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Derive the conditions $xy<1$ for $\tan^{-1}x+\tan^{-1}y=\tan^{-1}\frac{x+y}{1-xy}$ and $xy>-1$ for $\tan^{-1}x-\tan^{-1}y=\tan^{-1}\frac{x-y}{1+xy}$

Awarded 2 hours ago

Sooraj S

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Is tautological bundle $\mathcal{O}(1)$ or $\mathcal{O}(-1)$?

Awarded 3 hours ago

Li Yutong

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Is the convex hull of a compact set compact?

Awarded 9 hours ago

s.harp

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What's "the most right" symbol to use for "defined to be equal to"?

Awarded 11 hours ago

user132181

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Suppose you roll a pair of fair dice. What is the probability that the number of dots on the two dice sum to either $5$ or $10$?

Awarded 13 hours ago

Need Help

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What does pairwise disjoint mean?

Awarded 14 hours ago

Alan Sda

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3 point to circle. And get radius [duplicate]

Awarded 15 hours ago

eKKiM

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Why is $X^T X$ a symmetric matrix?

Awarded 17 hours ago

Thev

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Help with Math notation: what is ψ & ϕ in this example? [closed]

Awarded 23 hours ago

Axle Max

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Proving vector calculus identity $\nabla \times (\mathbf a\times \mathbf b) =\cdots$ using Levi-Civita symbol

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Theorem

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Correct name of an irregular pentagon with four vertices in a square shape and one protruding perpendicular from the mid point of two of the vertices?

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Morgoth

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Finding the angle between a line and a plane

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inoi

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Can anyone give me x,y coordinates for an octagon?

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MathGuy

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Showing that the closure of the closure of a set is its closure

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Alex Petzke

8,6536 gold badges63 silver badges92 bronze badges

How do 3 points define a plane?

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AnkitSablok

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Deriving the normal distance from the origin to the decision surface

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BitRiver

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Inner product of symmetric and anti-symmetric tensors

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user182595

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"If P, then Q; If P, then R; Therefore: If Q, then R." Fallacy and Transitivity

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David Marlowe

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$(XY)^*=X^* Y^*$?

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Jeff Faraci

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Correlation and dependence between $X$ and $Y:=X^2$

Awarded 2 days ago

TheHopefulActuary

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Trace of a nilpotent matrix is zero. [duplicate]

Awarded 2 days ago

Sam

1,1501 gold badge9 silver badges19 bronze badges

Why sum of interior angles in convex polygon is $(n-2)\cdot 180$

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someone123123

1,3493 gold badges11 silver badges24 bronze badges

Does absolute divergence imply divergence?

Awarded 2 days ago

StatsNoob

2051 gold badge2 silver badges9 bronze badges

What is the Hilbert curve's equation?

Awarded 2 days ago

PyRulez

10.1k4 gold badges37 silver badges102 bronze badges

Propositional Logic - Associative Property question

Awarded 2 days ago

papercuts

1,8438 gold badges27 silver badges27 bronze badges

Each limit represents the derivative of some function $f$ at some number $a.$ State $f$ and $a$ in each case. [closed]

Awarded 2 days ago

user165349

11 gold badge1 silver badge4 bronze badges

Calculating the Value of a complex limit

Awarded 2 days ago

Jordan N

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A good quick introduction to Knot Theory?

Awarded 2 days ago

Ritwik Bose

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Why is absolute value function not a polynomial? [closed]

Awarded 2 days ago

user373141

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Is there a bijection between $[0, \infty)$ and $(0,1)$ [duplicate]

Awarded 2 days ago

qwerty

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Subgroup of $\mathbb{R}$ either dense or has a least positive element?

Awarded 2 days ago

Seohyun

3931 gold badge4 silver badges4 bronze badges

How do I find the start and end point of an Arc? Using center xy, radius and start/end angle values.

Awarded Sep 26 at 13:05

01AutoMonkey

3072 gold badges4 silver badges10 bronze badges

How to find the length of the line segment of this following triangle?

Awarded Sep 26 at 12:05

akusaja

2,5216 gold badges28 silver badges38 bronze badges

Show that the equation has at most two real roots, using the mean value theorem.

Awarded Sep 26 at 7:27

C_Lodge

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How to show that $(-a)(-b)=ab$ holds in a field? [closed]

Awarded Sep 26 at 5:10

Cosapp

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What is mathematical basis for the percent symbol (%)?

Awarded Sep 25 at 22:08

DQdlM

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Permutation of multiset

Awarded Sep 25 at 21:43

Nighty

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Mathematics Engineering: How do you prove the power rule?

Awarded Sep 25 at 20:53

Sony

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Examples of Linear Transformation problem

Awarded Sep 25 at 17:46

SubbaKudmi

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prove that if $a=b$ then $a+c=b+c$ where $a,b,c\in \mathbb R$

Awarded Sep 25 at 12:46

thomson

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1 minus percentage: What is this called?

Awarded Sep 25 at 12:46

User1974

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Abbreviated notation for "vector normalized by its length" (unit vector)

Awarded Sep 25 at 12:46

bers

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Why are angles in "degrees" dimensionless?

Awarded Sep 25 at 4:16

seeker

6,60712 gold badges71 silver badges106 bronze badges

Scheme of finite type over a field $K$ v.s. $K$-scheme

Awarded Sep 25 at 4:16

Bogdan

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Why is this translation not a linear transformation? [closed]

Awarded Sep 25 at 2:10

Kanokpon Arm

4431 gold badge3 silver badges8 bronze badges

Is there a subset of a non regular language that is regular

Awarded Sep 25 at 0:57

user34790

4,1025 gold badges22 silver badges29 bronze badges

Estimate or calculate the number of digits of a multiplication

Awarded Sep 24 at 19:55

Trux

1,4891 gold badge13 silver badges24 bronze badges

Finding the solution of a differential equation that passes through a point

Awarded Sep 24 at 19:55

Fernando Martinez

6,55018 gold badges74 silver badges106 bronze badges

Probability of drawing exactly $1$ ace upon drawing $2$ cards from a deck

Awarded Sep 24 at 18:32

E. Sundin

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Example of application of limit in daily life

Awarded Sep 24 at 16:20

user307537

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What are the mean and variance of the log of a random variable?

Awarded Sep 24 at 15:05

user3722235

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Finding Number of Automorphisms of Z8?

Awarded Sep 24 at 14:07

anon_swe

6755 gold badges13 silver badges22 bronze badges

Find the radius of convergence and the interval of convergence for the following power series $\sum_{n=1}^{\infty} \frac{(2x-1)^n}{5^n \sqrt{n}}$

Awarded Sep 24 at 13:35

Tinler

1,0491 gold badge11 silver badges23 bronze badges

Proving set of interiors is open

Awarded Sep 24 at 13:01

Wolfy

6,3655 gold badges40 silver badges104 bronze badges

Prove the first absorption law by showing that if A and B are sets, then A ∪ (A ∩ B) = A [duplicate]

Awarded Sep 24 at 13:01

ComputerLocus

2736 gold badges8 silver badges17 bronze badges

Integration of $\int\log(\sqrt{1-x}+\sqrt{1+x}) \, dx$

Awarded Sep 24 at 12:20

Pratyush

2,5663 gold badges23 silver badges47 bronze badges

Can we write a complex number z like this Re(z)+Im(z)?

Awarded Sep 24 at 12:05

GniruT

9672 gold badges12 silver badges21 bronze badges

Implication Logic Truth Table Explained

Awarded Sep 24 at 4:36

Javed Iqbal

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