Support · Mathematics Standard 11–12 – Year 12 – Standard 2 · Trigonometry
Support Apply the formula A = 1/2absinC, where a and b are the sides that form the included angle C in a given triangle ABC, to solve problems in a range of contexts
Resources for the prerequisite content of this dot point: earlier-stage (or earlier sub-level) dot points in the same strand that students usually need first. Use these to fill gaps before or alongside the core lesson.
Prerequisite links are draft mappings generated from the syllabus structure (earlier stage, same strand, closest content). They are being reviewed by teachers. Spot a poor match? Tell us.
Prerequisite dot points
Apply the formula A = 1/2absinC, where a and b are the sides that form angle C to find the area of a given triangle ABC
Stage 5 · Trigonometry C (Path) Draft mapping
- Interactive toolStarterMaths Is Fun: Area of a triangle (½ab sin C)Use it for: Area rule for non-right triangles.
- Corbettmaths practice questions: Trigonometry: sine rule (sides)Use it for: Free printable graded practice questions (with answers) on trigonometry: sine rule (sides) for drill or a quick check.
- WorksheetDrillKuta free worksheet: Trigonometry and areaUse it for: Printable skills-practice sheet with answer key on trigonometry and area; good for drill or homework.
- VideoStarterCorbettmaths video: Trigonometry: area of a triangleUse it for: Short worked-example video on trigonometry: area of a triangle to model the method before practice or for flipped revision.
Apply the cosine rule to find the unknown sides for a given triangle ABC.
Stage 5 · Trigonometry C (Path) Draft mapping
- Interactive toolStarterMaths Is Fun: The law of cosinesUse it for: Cosine rule with examples.
- Corbettmaths practice questions: Trigonometry: sine rule (sides)Use it for: Free printable graded practice questions (with answers) on trigonometry: sine rule (sides) for drill or a quick check.
- VideoStarterCorbettmaths video: Trigonometry: cosine rule (sides)Use it for: Short worked-example video on trigonometry: cosine rule (sides) to model the method before practice or for flipped revision.
Use graphing applications to verify the area rule A = 1/2absinC.
Stage 5 · Trigonometry C (Path) Draft mapping
- Desmos Graphing CalculatorUse it for: Graph lines, parabolas and exponentials live; find intersections to solve simultaneous equations.
- Interactive toolEnrichmentGeoGebra ClassicUse it for: Dynamic geometry and graphing for constructions and proofs.