During one of our assignments, I came across a short TED talk by Terry Moore called "Why is 'x' the unknown?" During this 4 minute video, he explains how x actually originated in the Arabic word for "the unknown thing" that couldn't be directly translating into any European language, since there was no equivalent character to represent it. To solve this problem, they use the Greek letter chi ( χ ), and I'm sure you can guess the rest from there. I have often heard students ask why we always seem to use x, and I remember wondering that myself when I was in high school. Usually, teachers would answer something like, who knows? or they just really liked that letter. Well, now you can tell your students the real answer!
On that note,
I love the picture! I've seen that floating around online before! Good post - I actually had some grade nine students ask me that the other day...I didn't have an answer, and now I do. Thanks!
ReplyDeleteI never knew why we use "x." Thank you for this information. I will definately be sharing it with my students.
ReplyDeleteSo great! It reminded me of a PD session I was in recently where a colleague of mine asked the two math consultants and the room full of Intermediate math educators why we use "m" in the formula for slope of a line. No one had a definitive answer and they moved on but curiosity got the better of me and I needed to know. Turns out the m derives from the French word "monter" which means to climb and which makes perfect sense. It was an aha moment for me - love those moments!
ReplyDeleteI always asked myself this in high school too!!! Thats very interesting.
ReplyDeleteReading this post and looking at the picture you posted made me think about this:
http://www.google.ca/url?sa=i&rct=j&q=find+x+joke&source=images&cd=&docid=lcbvusVQNqmIhM&tbnid=yyIwsz88W-yeQM:&ved=0CAUQjRw&url=http%3A%2F%2Fwww.guzer.com%2Fpictures%2Ffindx.php&ei=YpKXU8fnJo2iqAajtYDgDA&bvm=bv.68693194,d.b2U&psig=AFQjCNGihQ8toVp1f0OCd2_6_UizaWQAow&ust=1402528735221681
Pretty funny and witty!