Inquiry Activity Summary
"sin²x+cos²x=1" comes from the identity (proven factor or formula) of the Pythagorean Theorem. The theorem, when involving the trig ratios of the Unit Circle, is written in the form of "x²+y²=r²". In order to get the set of values to equal "1", we must divide the entire equation by "r²". As a result, we are left with two ratios, "x/r" (cosine), and "y/r" (sine).
Inquiry Activity Reflection
If I had to describe trigonometry in THREE words, they would be: patterns, formulas, and memorization.