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Thursday, July 19, 2018

Problem of the Week 7-19-18: Invertible Matrix [Linear Algebra]

Check out this Problem of the Week.
Be sure to let us know how you solved it in the comments below or on social media!

Solution below:

*Note: In the video, k- 1 - 6(k - 1) reduces to k2- 6k + 5 NOT k2 - 6k - 5

Friday, July 13, 2018

Unlucky Numbers Around the World

Friday the 13th is upon us!  Across the nation, there are people avoiding black cats, spilled salt, ladders, and broken mirrors. Not everyone, however, is scared of 13 because they have other numbers to fear. 

In honor of today, here are 6 unlucky numbers from around the world.

4 - China
In China, the number 4 is considered unlucky because it is homophonous to the word "death." Similar to how the 13th floor is absent in many buildings in the West, the 4th floor is often left out in China.

9 - Japan
Just like the number 4 in China, the number 9 is a bad omen in Japan because it sounds similar to the Japanese word for “torture.”

17 - Italy
The Roman numeral for 17 is XVII, and an anagram for XVII is "VIXI.” This translates to “I lived," aka “my life is over."

26  - India 
For India, tragedies and disasters have the pattern of striking on the 26th (the 2008 Mumbai terror attack, the 2001 Gujarat earthquake, the 2004 Indian Ocean tsunami, 2008 Ahmedabad bomb blasts). For this reason, India doesn't really like the number 26. Can you blame them?

39 - Afghanistan
The number 39 is considered cursed in Afghanistan due to the fact that 39 translates to  ‘morda gow’ which means ‘dead cow” - which is slang for pimp. Since 39 is linked to prostitution, the number is largely avoided.

0888 888 888 - Bulgaria
After three people in Bulgaria with the phone number 0888 888 888 died within ten years, a Bulgarian mobile company suspended the phone number because they believed it was cursed. If you are in Bulgaria, try calling the number. Surely, no one will pick up. 

Thursday, July 12, 2018

Advanced Knowledge Problem of the Week 7-12-18: Root Existence for a Polynomial [Real Analysis]

Check out this Advanced Knowledge Problem of the Week.
Be sure to let us know how you solved it in the comments below or on social media!

Solution below.

Tuesday, July 10, 2018

Thursday, July 5, 2018