Best of 2009

The blog posts Hacker News loved most in 2009. 1,923 posts.

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278

Step-by-Step Math

Have you ever given up working on a math problem because you couldn’t figure out the next step? Wolfram|Alpha can guide you step by step through the process of solving many mathematical problems, from solving a simple quadratic equation to taking the integral of a complex function.

292

An almost perfect real-world hack

Almost immediately after we bought our house I received a letter in the mail. The local school district was appealing the tax assessment of my house. The issue in question was the value of my property in 2002 (don’t ask, it’s a long story, and a silly law). My property tax is some percentage of the 2002 value of my…

293

Xkcd meets reality

Earlier this week, xkcd posted a fantastic comic about the apocalypse happening and the dead rising to walk the earth. In the comic, mathematicians scribbled frantically and raced to Paul Erdos’ grave to get him to sign a document that is presumably co-authorship on a paper. (For the uninitiated, read about the Erdos…