User:Temperal/The Problem Solver's Resource1
Introduction | Other Tips and Tricks | Methods of Proof | You are currently viewing page 1. |
Trigonometric Formulas
Note that all measurements are in radians.
Basic Facts
The above can all be seen clearly by examining the graphs or plotting on a unit circle - the reader can figure that out themselves.
Terminology and Notation
, but $\cot A\ne\tan^{-1} A}$ (Error compiling LaTeX. Unknown error_msg), the former being the reciprocal and the latter the inverse.
, but $\csc A\ne\sin^{-1} A}$ (Error compiling LaTeX. Unknown error_msg).
, but $\sec A\ne\cos^{-1} A}$ (Error compiling LaTeX. Unknown error_msg).
Speaking of inverses:
Sum of Angle Formulas
or
or
Pythagorean identities
for all .
Other Formulas
Law of Cosines
In a triangle with sides ,
, and
opposite angles
,
, and
, respectively,
and:
Law of Sines
Law of Tangents
For any and
such that
,
Area of a Triangle
The area of a triangle can be found by