Mathematics — first biennium · Lesson
A sign chart starts from the critical points of the factors. For a quotient, denominator zeros are excluded, while numerator zeros may be included when equality is allowed.
Prerequisites: Linear inequalities and factorization
Goal: Build a sign chart from the critical points of linear factors.
In this lesson: Build a sign chart from the critical points of linear factors.
New concept: Critical points are the zeros of the factors and, for quotients, also denominator zeros. Ordering them on the number line splits x-values into intervals where each factor keeps a constant sign.
How to proceed: For a product, both zeros may be included because the symbol is ≥.
You can already assume: Linear inequalities and factorization.
Completed exercises: 0/5 · Correct on first attempt: 0
For a product, both zeros may be included because the symbol is ≥.
Data / situation: Solve (x-(-3))(x-(-1))≥0.
ConceptStep separates what is required from what is recommended or useful as reinforcement. Only required prerequisites block your progress.
Relationships: solid line = required · dashed line = recommended · dotted line = reinforcement.