Barrons AP Calculus - David Bock

25.

26.

27. sin (π − α) = sin α; cos (π − α) = −cos α.


28. sin (π + α) = −sin α; cos (π + α) = −cos α.


29. LAW OF COSINES. c^2 = a^2 + b^2 − 2ab cos C.


30. LAW OF SINES.


31. The area sin C.

GRAPHS OF TRIGONOMETRIC FUNCTIONS

The four functions sketched above, sin, cos, csc, and sec, all have period 2π.