Answer:
The correct answer is:
Error made: The student multiplied only corresponding terms in each bracket with each other
Correction: Each term in one bracket is to be multiplied with every term in the next bracket
Step-by-step explanation:
The student paired the terms in the brackets into like terms and multiplied the like terms like this:
(2x + 2) × (4x - 1)
collecting like terms: (2x, 4x) (2, -1)
(2x × 4x) (2 × (-1)) = 8x² - 2.
The above is the wrong way of expanding the bracket. The correct way of doing it is as follows:
(2x + 2) (4x - 1)
Each term in one bracket multiplies each term in the second bracket.
= 2x (4x - 1) + 2(4x -1)
= 8x² - 2x + 8x - 2
= 8x² + 6x - 2