Multiplying polynomials
· When multiplying 2 binomials, we use F.O.I.L as in first, outside, inside and last (also known as distributive property)
Example
(3x+7)(x-5)
F: (3x)(x) + O: (3x)(-5) + I: (7)(x) + L: (7)(-5)
= (3x)(x) + (3x)(-5) + (7)(x) + (7)(-5)
= 3x2 – 15x + 7x – 35
= 3x2 – 8x – 35
Example
(3x+7)(x-5)
F: (3x)(x) + O: (3x)(-5) + I: (7)(x) + L: (7)(-5)
= (3x)(x) + (3x)(-5) + (7)(x) + (7)(-5)
= 3x2 – 15x + 7x – 35
= 3x2 – 8x – 35