CurriculumGrade 11Mathematics

Rational, Radical, and Function Operations

Aligned to F-BF.B.4 — Common Core State Standards for Mathematics.

What this lesson teaches

An inverse function undoes what the original function did, swapping inputs and outputs. If a function adds 3, its inverse subtracts 3. You can also combine functions by composing them, where the output of one becomes the input of the next.

Worked example

If f(x) = x + 3, then to undo it the inverse is f-inverse(x) = x - 3. Check: f(2) = 5, and the inverse takes 5 back to 2.

Practice questions

  1. Find the inverse of f(x) = x - 7.
  2. Find the inverse of f(x) = 2x.
  3. If f undoes g, what is f(g(4))?

Watch the lesson

Every lesson comes with a video taught in English and Spanish — the same video the QR code in the printed workbook opens.

▶ Watch this lesson

En español

Operaciones con Funciones Racionales, Radicales e Inversas

Una función inversa deshace lo que hizo la función original, intercambiando entradas y salidas. Si una función suma 3, su inversa resta 3. También puedes combinar funciones al componerlas, donde la salida de una se convierte en la entrada de la siguiente.

Ejemplo: Si f(x) = x + 3, entonces para deshacerla la inversa es f-inversa(x) = x - 3. Comprobación: f(2) = 5, y la inversa lleva 5 de regreso a 2.

Teach this lesson today

An AI tutor that guides with questions instead of just giving answers — all K–12 core subjects, every child in the family.

Start free — no card required