## Trigonometry – Cosine Double Angle Identity

Cosine Double Angle Identity In this tutorial students learn how to verify a trigonometric equation using trigonometric identities like Double Angle and Pythagorean. Virginia Standards of Learning (SOL) T.5 Key Skills Pythagorean Identities sin²x + cos²x = 1 1 + cot²x = csc²x tan²x + 1 = sec²x Trigonometric Identities 1/cos(x) = sec(x) 1/sin(x) = csc(x) tan(x)… Read More »