Jabarkan dan sederhanakan (x-2y+3z)²

(x-2y+3z)²
= (x-2y+3z)(x-2y+3z)
= x(x-2y+3z)-2y(x-2y+3z)+3z(x-2y+3z)
= x²-2xy+3xz-2xy+4y²-6yz+3xz-6yz+9z²
= x²-2xy-2xy+4y²-6yz-6yz+9z²+3xz+3xz
= x²-4xy+4y²-12yz+9z2+6xz