6-3 Double-Angle and Half-Angle Identities Section 6-3 Double-Angle and Half-Angle Identities
Explore/Discuss 472 6 TRIGONOMETRIC IDENTITIES AND CONDITIONAL EQUATIONS Or, if we use equation (3) in the form sin2 x 5 1 2 cos2 x and substitute it into equation (2), we get cos 2x 5 cos2 x 2 (1 2 cos2 x) On simplification, this gives cos 2x 5 2 cos2 x 2...