Starting today, I will be summarizing all the posts in this blog at the end of each month. I will be calling the summary Month in Review.

For January 2013, below is the list of posts in case you missed one.

- 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

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