\sin^4 x + \cos^4 x = (\sin^2 x + \cos^2 x)^2 - 2\sin^2 x \cos^2 x - AMAZONAWS Understanding the Identity: sin⁴x + cos⁴x = (sin²x + cos²x)² − 2sin²x cos²x 📅 March 6, 2026 👤 scraface Mar 06, 2026