Birthday Donation

My birthday party of this year was delayed.

A birthday present is common here for a birthday party. But I have all tangible things I want, except one. Yet, I want to have several non-tangible things. However, they are either impossible for a birthday presents or meaningless. For example, I would like to have world peace, a world class free education system in many languages, I want to understand some mathematical concepts, I would like to be fluent of German, I would like to have more time for my volunteer activities, and so on.

Thus, I asked some donation as a birthday present. I first show a list of organization I would like to donate. Then the people who join the party donate. I match the same amount from my pocket money to double the donation. This year was the second time. I think it went well. When I got a receipt from the organization, I will show it to the party participants. My cynical friends have already joke on them when they saw the paper, "it is just a paper and you can make it by the photoshop."

This time I was a bit afraid if the donation is too much. Then, I might not be able to pay the match, however, it was fine.

Comments

Why A^{T}A is invertible? (2) Linear Algebra

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Here is my question. The area of parallelogram is the difference of these two rectangles (red rectangle - blue rectangle). This is not intuitive for me. If you also think it is not so intuitive, you might interested in my slides. I try to explain this for hight school students. Slides: A bit intuitive (for me) explanation of area of parallelogram (to my site, external link) .

Lx=d: SundayResearch

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