Trigonometry 4.0 – Miscellaneous

Related tutorials

• Trigonometry 2.2 — Introduction to the Unit Circle (reference angle + ASTC + quadrant rules → all answers in a domain) → worth a recap before this lesson
• Trigonometry 4.1 — Compound Angle Formula → the next step after this one
• Trigonometry 4.4 — Quadratic Equations → the next step after this one
• Trigonometry 4.5 — Trig Proof 1: Prove `cos² A + sin² A = 1` (the Pythagorean trig identity; 🚨 LOAD-BEARING canonical LCHL proof — first of EIGHT trig proofs examinable at LCHL; uses the unit circle (page 13) + the distance-between-two-points formula (page 18); 🚨 the **chronological rule** — proving something on page 13 only permits use of page 13 formulae, not later pages, because the page-14/15/16 formulae are themselves derived from page 13) → the next step after this one