Trigonometry Flashcards
1
Q
Law of Cosines
A
c² = a² + b² - 2abcosC
2
Q
Remember to do what?
A
DRAW A PICTURE
3
Q
What is θR?
A
A reference angle between 0 and 2pi radians
4
Q
Area of a sector
A
A = 1/2 * r² * θ
5
Q
Arc length
A
l = rθ
6
Q
sin2x = ?
A
= 2(sinx)(cosx)
7
Q
cos2x = ?
A
= cos²x - sin²x = 2cos²x - 1 = 1 - 2sin²x
