Solve both parts and justify the conditions used. Part A: Explain why the sine rule in an SSA problem may give two triangles. Part B: Do equal magnitudes guarantee equal vectors? Give a counterexample.
- Use the domain, units and sampling assumptions stated in the question.
- Use the domain, units and sampling assumptions stated in the question.
Skills and prerequisite lessons
Working and explanation
BUILD THE REASONING
Hint 1
Hint 2
Worked solution
Part A reasoning
Translate the geometry or physical quantity into vectors and check angle conventions.
Calculate or simplify this relation.
A supplementary candidate is discarded if the angle sum makes it impossible.
Part B reasoning
Separate magnitude, direction and position; compare vectors by displacement.
Calculate or simplify this relation.
The two perpendicular nonzero vectors cannot be equal.
A: Both B and 180°−B have the same sine; each must be checked against the remaining angle and side conditions. B: No: (10,0) and (0,10) have different directions.
Checks and common pitfalls: A supplementary candidate is discarded if the angle sum makes it impossible. The two perpendicular nonzero vectors cannot be equal.
Reasoning checklist · self / teacher assessment
- Solve part A with its stated restrictions.
- Solve part B using an appropriate representation.
- Give the reasoning and check conditions in both parts.
Think first. Reveal a hint when the class is ready.