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Inverse functions

Grade 10-11

What this lesson shows

f(x) = 2x + 1. Feed it 3: times 2 is 6, plus 1… 7. Now the real question: if all you know is the OUTPUT, 7… can you get back to the 3?

Try it yourself

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

  1. Range of f(x) = x² + (-5)
    Show answer
    y ≥ -5
  2. f(x) = x + 1. Find f⁻¹(1)
    Show answer
    0
  3. f(x) = x + 1. Find f⁻¹(2)
    Show answer
    1
  4. Range of f(x) = x² + 3
    Show answer
    y ≥ 3

Practise this every day

Eduyro gives your child a short daily worksheet on exactly this skill, and moves them on only once they have it. Watch the lesson, then build the fluency.

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