Range of a quadratic

What this lesson shows

y = x² − 4. Here's a question about the WHOLE curve at once: which heights does it actually reach… and which does it never touch?

Try it yourself

Real questions from this lesson's worksheets — answers below each one.

1. Range of f(x) = x² + 1
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   y ≥ 1
2. Range of f(x) = x² + 2
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   y ≥ 2
3. Domain of f(x) = 1/(x - 25)
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   x ≠ 25
4. Which function has range y ≥ 4?
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   x² + 4