Double Angle Flashcards
(5 cards)
1
Q
What is the identity for cos(2u) using cos²(u) and sin²(u)?
A
cos(2u) = cos²(u) − sin²(u)
2
Q
What is the identity for cos(2u) using only cos²(u)?
A
cos(2u) = 2cos²(u) − 1
3
Q
What is the identity for cos(2u) using only sin²(u)?
A
cos(2u) = 1 − 2sin²(u)
4
Q
What is the identity for sin(2u)?
A
sin(2u) = 2sin(u)cos(u)
5
Q
What is the identity for tan(2u)?
A
tan(2u) = (2tan(u)) / (1 − tan²(u))