6 (a) Simplify: (i) 3a × 4 (ii) b × b × b × b (iii) c² × c⁴ (b) Factorise: 9 - 6y - OCR - GCSE Maths - Question 6 - 2023 - Paper 3

This expression consists of four factors of b. We can write this using exponents:

$b imes b imes b imes b = b^4$

When multiplying terms with the same base, we add the exponents:

$c^2 imes c^4 = c^{2+4} = c^6$

First, identify the common factors in the expression. Here, both terms have a common factor of 3:

$9 - 6y = 3(3 - 2y)$