I also 'wing it' a bit, working example problems I've never done before, so that you can see that even Trig Masters don't always see exactly how to solve a proof when they first see it, and that often it comes down to 'messing around with it' and trying a few things before you find the path that will get you to the solution. Most notably are the half-angle and double-angle formulas. Click on Open button to open and print to worksheet.

The reality is that trig proofs are tough, even for teachers, and the only reason the teacher can make it look so easy is they've been teaching the same problems year after year! That's why in the videos below I break trig proofs down for you, revealing the Big Three basic types of trig proof that almost every proof falls into, and showing you the step-by-step process for working each type out. There are many important trig formulas that you will use occasionally in a calculus class. Worksheets are Honors precalculus prove the following identities, Trigonometry packet geometry honors, Trig packet, Trigonometric formula de nition of the trig functions, Spherical trigonometry, Geometry beginning proofs packet 1, Trig substitution, Trig cheat. Trig Proofs & Identities: 3 Tricks to Make Them Easier The biggest problem with trig proofs (other than the word 'proof' causing flashbacks to geometry) is that teachers tend to make them look way too easy in class, so students get discouraged when they can't just whip them off the top of their heads like Teacher. Harold's Triangles Cheat Sheet: Docx: Law of Sines, Cosines and Tangents: Harold's Trig Proofs Cheat Sheet: Docx: My proofs of three (3) trig formulas that allow us to easily derive ALL the trig formulas: Harold's Precalculus Cheat Sheet: Docx: My rectangular, polar, and parametric coordinate equations for conics sections: Harold's Exponential.

Proofs cheat sheet trig