Written working: rewriting one plus or minus sine double angle
Student Activity 𝅛 Perfect-square Structure 𝅛 Exam-quality Working 𝅛 Follow-up ⭕ Learning Focus SL and HL students: (no additional HL content) • transforming a constant using the Pythagorean identity • recognising a perfect-square trinomial • distinguishing \displaystyle 1\pm\sin2x from \displaystyle 1\pm\cos2x • choosing algebraic structure after applying an identity • communicating a concise derivation The strategy...