Module 1.2 Algebra

Algebra carries the largest share of Module 1 questions. Category A only needs simple expressions; B1, B2, B2L and B3 also need equations, indices, logarithms and number systems.

Knowledge levels

Item	A	B1	B2 / B2L	B3
1.2(a) Simple algebraic expressions: evaluating, +, −, ×, ÷, brackets, simple algebraic fractions	1	2	2	2
1.2(b) Equations: linear and simultaneous equations, second-degree equations, indices, binary and other number systems, logarithms	—	1	1	1

Evaluating expressions

Substitute the numbers, then apply BODMAS.

Worked example

Evaluate 3a² − 2b when a = 4 and b = 5.

• a² = 16, so 3a² = 48
• 2b = 10
• Result = 48 − 10 = 38

Trap: (3a)² = 144 gives 134. The power applies only to a.