Question

упростите выражение 2a(a+b-c)-2b(a-b-c)+2c(a-b+c)

Answer 1

2a(a+b-c)-2b(a-b-c)+2c(a-b+c)=2a²+2ab-2ac-2ab+2b²+2bc+2ac-2bc+2c²=2a²+2b²+2c²