For $\cos 225^\circ$, since $225^\circ = 180^\circ + 45^\circ$, we use the cosine angle addition identity: - AMAZONAWS

📅 March 11, 2026 👤 scraface

Mar 11, 2026

$For $\cos 225^\circ$, since $225^\circ = 180^\circ + 45^\circ$, we use the cosine angle addition identity:$