Sal Khan
A detailed look at shapes that are prevalent in science: conic sections. You've seen circles your entire life. You've even studied them a bit in math class. Now we go further, taking a deep look at the equations of circles. Source: Khan Academy (www.khanacademy.org), used under the Creative Commons Attribution-NonCommercial-ShareAlike (CC BY-NC-SA) license. All Khan Academy content is available for free at www.khanacademy.org. Khan Academy does not endorse the World Public Library.
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