User Isaac

18 votes

Accepted

What is wrong in my proof that 90 = 95? Or is it correct?

answered Oct 22, 2010 at 11:00

18 votes

On applying the quadratic formula to a first-degree equation

answered Aug 16, 2010 at 7:46

18 votes

I want to find $\lim\limits_{x\to 5}\frac{2^x-2^5}{x-5}$ without using l'Hopital's rule

answered Jan 20, 2011 at 16:00

17 votes

Accepted

The cow in the field problem (intersecting circular areas)

answered Jul 20, 2010 at 20:48

16 votes

How can I understand and prove the "sum and difference formulas" in trigonometry?

answered Jul 31, 2010 at 7:51

16 votes

I need mathematical proof that the distance from zero to 1 is the equal to the distance from 1 to 2

answered Jun 26, 2011 at 7:41

15 votes

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For a polynomial $P$ for which $P(x+5) - P(x) = 2 ,\forall x$. What is the least possible value of $P(4) - P(2)$?

answered Feb 11, 2012 at 7:02

15 votes

Derivation of the formula for the vertex of a parabola

answered Jul 26, 2010 at 8:05

15 votes

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How many ways are there to define sine and cosine?

answered Aug 26, 2010 at 6:38

14 votes

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Proof of Angle in a Semi-Circle is of $90$ degrees

answered Jul 27, 2010 at 10:02

14 votes

Software for drawing geometry diagrams

answered Aug 10, 2010 at 6:32

13 votes

How do you define functions for non-mathematicians?

answered Aug 6, 2010 at 15:40

13 votes

What does it mean to be going 40 mph (or 64 kph, etc.) at a given moment?

answered Jul 26, 2010 at 20:36

13 votes

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Rotations by degrees other than $90, 180,$ and $270$.

answered Sep 3, 2010 at 5:29

13 votes

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What is the standard interpretation of order of operations for the basic arithmetic operations?

answered May 1, 2011 at 20:35

13 votes

Calculus question

answered Jun 17, 2011 at 2:40

12 votes

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Shortest way to achieve target angle

answered Feb 17, 2012 at 3:30

12 votes

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Polar equation of a circle

answered Jun 6, 2012 at 4:55

12 votes

Equation of angle bisector, given the equations of two lines in 2D

answered May 13, 2011 at 4:39

12 votes

Why don't these limits exist?

answered Mar 21, 2011 at 8:31

12 votes

Why are there 12 pentagons and 20 hexagons on a soccer ball?

answered Jan 20, 2011 at 19:05

12 votes

maximum area of three circles

answered Jan 4, 2011 at 4:55

12 votes

Odds of Winning the Lottery Using the Same Numbers Repeatedly Better/Worse?

answered Jan 6, 2011 at 17:03

12 votes

If $x=1$, then its powers end with $1$

answered Sep 18, 2010 at 17:29

12 votes

Compass-and-straightedge construction of the square root of a given line?

answered Jul 26, 2010 at 7:29

12 votes

Software for drawing geometry diagrams

answered Aug 10, 2010 at 0:46

11 votes

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Implicit Differentiation

answered Oct 24, 2010 at 20:26

10 votes

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Family of functions with two horizontal asymptotes

answered Aug 13, 2010 at 15:47

10 votes

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Why not write the solutions of a cubic this way?

answered Jan 25, 2011 at 6:52

9 votes

Calculating a Point that lies on an Ellipse given an Angle

answered Feb 14, 2011 at 23:32

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462 Answers

What is wrong in my proof that 90 = 95? Or is it correct?

On applying the quadratic formula to a first-degree equation

I want to find $\lim\limits_{x\to 5}\frac{2^x-2^5}{x-5}$ without using l'Hopital's rule

The cow in the field problem (intersecting circular areas)

How can I understand and prove the "sum and difference formulas" in trigonometry?

I need mathematical proof that the distance from zero to 1 is the equal to the distance from 1 to 2

For a polynomial $P$ for which $P(x+5) - P(x) = 2 ,\forall x$. What is the least possible value of $P(4) - P(2)$?

Derivation of the formula for the vertex of a parabola

How many ways are there to define sine and cosine?

Proof of Angle in a Semi-Circle is of $90$ degrees

Software for drawing geometry diagrams

How do you define functions for non-mathematicians?

What does it mean to be going 40 mph (or 64 kph, etc.) at a given moment?

Rotations by degrees other than $90, 180,$ and $270$.

What is the standard interpretation of order of operations for the basic arithmetic operations?

Calculus question

Shortest way to achieve target angle

Polar equation of a circle

Equation of angle bisector, given the equations of two lines in 2D

Why don't these limits exist?

Why are there 12 pentagons and 20 hexagons on a soccer ball?

maximum area of three circles

Odds of Winning the Lottery Using the Same Numbers Repeatedly Better/Worse?

If $x=1$, then its powers end with $1$

Compass-and-straightedge construction of the square root of a given line?

Software for drawing geometry diagrams

Implicit Differentiation

Family of functions with two horizontal asymptotes

Why not write the solutions of a cubic this way?

Calculating a Point that lies on an Ellipse given an Angle