Lesson 25 Triangle ratios
Lesson plan
| Piagetian Level | Learners Thinking and abstract of the activity | ||
|---|---|---|---|
| 3 B Mature Formal |
 Reflection on limits of sine and tan relations |
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| Prediction in terms of tangent ratio | Inverting the sine ratio | ||
| 3A Early Formal |
 Looking for ratio as independent of size |
Comparing tangent and sine ratios to predict values, with rounding, for 45° | |
Constriction of triangles |
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| 2B* Concrete Generalisation |
Interpretation in terms of same ratio of sides |
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| 2B Mature concrete |
Interpretation in terms of similarity | ||
| Middle concrete |
Episode 1 Similar triangles |
Episode 2 Exploring the tangent |
Episode 3 Exploring the sine ratio |