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Calculate the discriminant.

Read the idea, work independently, then explain what changed.

TOPIC 01

Quadratic equations and functions

A negative discriminant does not mean there are no complex roots.

PREDICT → MOVE → EXPLAIN

What does each coefficient change?

Before moving a slider, predict the opening, vertex and intercepts. Then compare the graph with your prediction.

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Try it. Leave your reasoning visible.

Use one hint at a time. A correction explains what changed, not just the final answer.

01 / Foundation#Your turn

Calculate the discriminant.

x2+2x+5=0x^2+2x+5=0

Working and explanation

BUILD THE REASONING

Hint 1
Use b²−4ac.
Hint 2
Here a=1,b=2,c=5.
Worked solution
  1. Substitute the coefficients.

    Δ=22−4(1)(5)\Delta=2^2-4(1)(5)
  2. A negative value excludes real roots.

    Δ=−16<0\Delta=-16<0

Discriminant −16; no real roots.

Checks and common pitfalls: A negative discriminant does not mean there are no complex roots.

Think first. Reveal a hint when the class is ready.

Focus on one question

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Curriculum and source notes ↗