Question

1. Uprość :
(a-2) do potęgi 2 - (a-1)(a+5)+(a-3)(a+3)

Answer 1

(a-2)^2 -(a-1)(a+5)+(a-3)(a+3)=
=a^2-4a+4-(a^2+5a-a-5)+a^2-9=
=a^2-4a+4-(a^2+4a-5)+a^2-9=
=a^2-4a+4-a^2-4a+5+a^2-9=
=a^2-8a