Geometric Proof of Pythagorean Identities

Explanations 3

• The Pythagorean identities state that sin⁡2θ+cos⁡2θ=1\begin{align*} \sin^2 \theta+\cos^2 \theta &= 1 \\ \end{align*}sin2θ+cos2θ​=1​ Simple, right? The proof isn't that difficult…

  By Anthony Jiang

• For the right Triangle XYZXYZXYZ, with angles x,y,x, y,x,y, and zzz, If sin(x)=4/5sin (x)= 4/5sin(x)=4/5 what is cos(x)cos (x)cos(x)?

  By Neelesh Ramachandran

• Here are some practice problems with pythagorean identities! Keep in mind that they mostly use the ones involving secants and cosecants. Remember that you can derive them from t…

  By Freya Edholm