A unit circle is an important part of trigonometry and can define right angle relationships known as sine, cosine and tangent.

Part of that is the way it's taught. Students are taught the "unit circle" and its relationship to trigonometry, but many fail to make the leap on how crucial circles are for trig functions. With ...

I'm talking about trigonometry, of course: that bastion of angles and triangles that is essential to calculating velocity, momentum, and much more.

This linear functional is, in fact, a Schwartz distribution. If the polynomials are orthogonal in the classical sense, then the classical weight function can be recovered from the distributional one ...

The first identity is the foundation of trigonometry, representing the relationship between sine and cosine on the unit circle.