- 2017: 01 02 03 04 05 06 07 08 09 10 11 12
- 2016: 01 02 03 04 05 06 07 08 09 10 11 12
- 2015: 01 02 03 04 05 06 07 08 09 10 11 12
- 2014: 01 02 03 04 05 06 07 08 09 10 11 12
- 2013: 01 02 03 04 05 06 07 08 09 10 11 12
- 2012: 01 02 03 04 05 06 07 08 09 10 11 12
January 2017
October 2016
September 2016
August 2016
June 2016
April 2016
February 2016
January 2016
December 2015
- Year 2015 in Review - Complete List of Posts
- Proof that the nth root of a times nth root of b is equal to nth root of ab
- Difference of 3-Digit Numbers with Reversed Digits
- The Sum of Two 2-Digit Numbers with Reversed Digits
- The Sum of Two Consecutive Odd Numbers
July 2015
June 2015
- Slope of Perpendicular Lines Theorem
- The Sum and Product of Roots Theorem
- Sample Proof on Triangle Congruence Part 3
May 2015
April 2015
March 2015
February 2015
January 2015
December 2014
November 2014
October 2014
- Quadrilaterals With Congruent Opposite Angles Are Parallelogram
- Congruent Opposite Sides of Quadrilaterals are Parallel
September 2014
July 2014
June 2014
- Parallel Lines and Ratio Proof
- Proof that sin(-θ) = - sin(θ), cos(-θ) = cos(θ), and tan(-θ) = -tan(θ)
- Square of Odd Numbers Minus 1
- Euclid's Proposition 1: A More Detailed Discussion
May 2014
- How to Prove a Mathematical Theory
- Proof that Square of Even Number Is Even
- Proof of Divisibility by 8
April 2014
March 2014
February 2014
- The Proof of the Divisibility by 3
- The Explanation Behind Divisibility by 2
- A Detailed Proof about Congruent Angles
January 2014
December 2013
- 2013 Year in Review - The Most Popular Posts
- The Common Segment Theorem
- The Right Triangle Leg Leg Congruence Theorem
- Proof that the Product of Two Rational Numbers is Rational
- A Proof of the Arithmetic Mean Geometric Mean Inequality
- Proof That The Sum The First N Odd Integers is a Square
November 2013
- Proof That Any Number Raised to 0 Equals 1
- Video: The Man Behind the Proof of the Fermat's Last Theorem
- The General Formula of Polygonal Numbers
October 2013
- The Proof of the Side Splitter Theorem
- The Proof of the Cyclic Quadrilateral Theorem
- Mathematical Fallacy: A Classic Proof That 1 Equals 0
September 2013
- A Mathematical Proof that i^i is a Real Number
- The Diagonals of an Isosceles Trapezoid Are Congruent
- August 2013 - Month in Review
August 2013
- Proof that the Solution of 3^x = 8 is Irrational
- The Proof of the Hypotenuse Angle Theorem
- The Proof of the Right Triangle Altitude Theorem
- Derivation of the Proof of the Area of a Rectangle
- Proof That the Angle Sum of a Pentagram is 180 Degrees
- July 2013 - Month in Review
July 2013
- The Sum of Two Prime Numbers Greater than 2 is Even
- Reflection and the ABCD Theorem
- The Perpendicular Bisector of A Chord Passes The Center of a Circle
- The Proof of the Simpson Line Theorem
- The Proof of the Hypotenuse Leg Theorem
- The Proof of the Hinge Theorem
- Triangle Inequality and Its Proof
June 2013
- Month in Review - June 2013
- The Proof of the Third Case of the Inscribed Angle Theorem
- The Proof of the Second Case of the Inscribed Angle Theorem
- Tangent Theorem 2
- Tangent Theorem 1
- Diagonals of Parallelogram Bisect Each Other
- Quadrilaterals with Congruent Opposite Angles are Parallelograms
- Angle Measure and Side Length Relationship of a Triangle
- Triangles with Non Congruent Sides
- Quadrilateral with Congruent Opposite Sides are Parallelogram
- Month in Review - May 2013
May 2013
- Math Proof of the Week 1 Answer
- Deriving the Area of a Triangle using Trigonometry
- Proof That The Opposite Sides of a Parallelogram Are Congruent
- The Angle Secant Theorem
- Math Proof Problem of the Week 1
- New Series: Math Proof of the Week
- Proof that Equilateral Triangles are Equiangular
- The Proof of the Isosceles Triangle Theorem
- Proof by Contradiction: 0.999... = 1
- Arithmetic Mean Proof
April 2013
- Month in Review - April 2013
- The Closure Property of Positive Real Numbers Under Addition
- Proving the Perpendicular Bisector Theorem Using SAS Congruence
- Proving The Perpendicular Bisector Theorem by Reflection
- The Reflection Postulate
- Linking Triangle Angle Sum and Inscribed Angle Theorems
- The Properties of Reflection
- Proof that -(a + b) = (-a) + (-b)
- Proof that (-a)(-b) = ab
- The Product of Negative Number and a Positive Number is Negative
- Proof that the Product of Any Number and Zero is Zero
- The Proof of the Cancellation Law of Addition
March 2013
- Month in Review - March 2013
- The Axioms of Equality
- The Axioms of Real Numbers
- The Midpoints of the Sides of a Quadrilateral Form a Parallelogram
- The Proof of the Midsegment Theorem
- Representing the Sum and Difference of Two Squares
- Deriving the Area of a Circle -- Another Way
- The Derivation of the Area of a Circle
- The Opposite Sides of a Parallelogram are Congruent
- Using the Area of a Rectangle to Derive the Area of a Triangle
February 2013
- Month in Review - February 2013
- Making Connection Between Areas of Trapezoids and Parallelograms
- Derivation of the Area of a Trapezoid
- Proofs and Jokes Have a Lot in Common
- Derivation of the Area of a Parallelogram
- Like us on Facebook
- Deriving the Sum of the Geometric Sequence
- Deriving the Sum of the Arithmetic Sequence
- Sum of the First n Positive Integers: Another Solution
- Deriving the Formula of the Arithmetic Sequence
January 2013
- Month in Review - January 2013
- The Sum of the First n Positive Integers
- The Power Law of Logarithms
- The Quotient of Logarithm of A and Logarithm of B
- Proof that Vertical Angles Are Congruent
- A Geometric Proof of an Infinite Series
- Algebraic Proof: Diagonals of a Parallelogram Bisect Each Other
- Proof that Isosceles Trapezoids Have Congruent Base Angles
- 5 Help Tools for Learning Mathematical Proofs
December 2012
- Year in Review - The Most Popular Posts
- The Proof of the Midpoint Formula
- A Mathematical Proof that Two Equals One
- A Proof that Square Root of 2 Plus Square Root of 3 is Irrational
- Proof that Square Root of 6 is Irrational
- The Transitivity of Whole Numbers
- The Quadratic Formula Theorem
- The Inscribed Angle Theorem
- The Exterior Angle Theorem
- Proof that Square Root of Three is Irrational
- Proof that 0.999... = 1
- Derivation of the Cosine Law
- Derivation of the Law of Sines
November 2012
- The Sum of the Exterior Angles of a Polygon
- The Proof of the Polygon Angle Sum Theorem
- Proof of Angle Sum of Quadrilaterals
- Proof that The Sum of Two Odd Integers is Even
- The Pythagorean Theorem
- Star Polygon Angle Sum: Another Proof
- Reversing the Inequality Sign
- The Product of Logarithm of A and Logarithm of B
- Triangle Angle Sum Theorem: A More Friendly Proof
Pingback: Month in Review - February 2013 - Proofs from The Book
Pingback: Month in Review - March 2013 - Proofs from The Book
Pingback: Month in Review - June 2013 - Proofs from The Book