Formula Evaluation

Free interactive math game: Formula Evaluation — aₙ = 3n² − 5. Part of the Sequences category on MathKite.

Example problems

Taken from the generator that powers this exercise. A fresh set appears every time the page is opened, and the printable worksheet holds ten of them.

  1. General formula: aₙ = n² − 4 Find a₁₀ = ?
  2. General formula: aₙ = n² Find a₇ = ?
  3. General formula: aₙ = 2n² − 1 Find a₆ = ?
  4. General formula: aₙ = 3n − 5 Find a₃ = ?

About this exercise

Generating terms from a formula for the nth term.

How to solve it

Substitute the position number into the formula and evaluate it.

Worked example

With a formula of 3n + 2, the fourth term is 3 x 4 + 2 = 14.

Common mistake

Starting n at zero. Unless the question says otherwise, the first term is n equals 1.