Question

Упростить 3х(х+у+с)-3у(х-у-с)-3с(х+у-с)=

Answer 1

3x(x+y+c)-3y(x-y-c)-3c(x+y-c)=3cx+3x²+3xy+3cy-3xy+3y²+3c²-3cx-3cy=3c²+3x²+3y²

Answer 2

3x(x+y+c)-3y(x-y-c)-3c(x+y-c)=
3x^2+3xy+3xc-3xy+3y^2+3yc-3cx-3cy+3c^2=
3x^2+3y^2+3c^2=3(x^2+y^2+c^2).