Expansion of Algebraic Expressions - JSS2 Mathematics Lesson Note

Expansion of algebraic expressions involves removing the brackets by multiplying each term inside the bracket by the term outside.

Examples:

Example 1: 3(𝑎+2)

Expand by distributing 3 to both 𝑎 and 2:

3x𝑎+3x2=3𝑎+6

Example 2: (𝑥+3)(𝑥+4)

Apply the distributive property (FOIL method: First, Outer, Inner, Last):

𝑥 x 𝑥 + 𝑥 x 4 + 3 x 𝑥+ 3 x 4

= 𝑥2+4𝑥+3𝑥+12

=𝑥2+7𝑥+12