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General Information:

Over 3,800 Videos

Ourlibrary of videos covers K-12 math, science topics such as biology, chemistry, and physics, and even reaches into the humanities with playlists on finance and history. Each video is a digestible chunk, approximately 10 minutes long, and especially purposed for viewing on the computer.

You're joining millions of Khan Academy students from all over the world who learn at their own pace every single day.

By: Sal Khan, Monterey Institute for Technology and Education

Volume of a Sphere

A broad set of tutorials covering perimeter area and volume with and without algebra. Tired of perimeter and area and now want to measure 3-D space-take-upness. Well you've found the right tutorial. Enjoy!

A broad set of tutorials covering perimeter area and volume with and without algebra. Tired of perimeter and area and now want to measure 3-D space-take-upness. Well you've found the right tutorial. Enjoy!

A broad set of tutorials covering perimeter area and volume with and without algebra. Tired of perimeter and area and now want to measure 3-D space-take-upness. Well you've found the right tutorial. Enjoy!

Pythagoras had a problem with beans and irrationality. What really happened? I don't know! The square root of two is irrational, and beans are delicious.

Recreational mathematics and inspirational videos by resident mathemusician Vi Hart

Accuracy not guaranteed. Get Audacity and play! Correction: it is the Basilar membrane, which is what I say, but somehow between recording the script and actually drawing the stuff I got confused and thought I just pronounced my Vs poorly. Always sad to

Recreational mathematics and inspirational videos by resident mathemusician Vi Hart