For another example, pupils often generalise the distributive Ian from
2(x + y) = 2x + 2y to (× + y) 2 = × 2 +y 2. In such cases, it is not effective to just correct the
errors.
The pupils must confront their own thinking related to the errors.
Oliviers (1989)
provides further examples of common algebraic errors and argues that some errors arise
from correct pervious leaning.
For example, pupils who solve (x- 1) (× - 3) = 0 correctly with × - 1 = 0 or x - 3 = 0 will be puzzled why this correct Procedure leads to the wrong answers with (x - 1)(x - 3) = 5, for instance Suggest some ways to resolve this problem.