Question

Expand x-2y-3zsquare​

Answer 1

Explanation:

(x-2y-3z)²

={(x-2y)-3z}² (taking x-2y as "a" and 3z as "b")

=(x-2y)²+(3z)²-2(x-2y)(3z)

={(x)²+(2y)²-2×x×2y}+9z²-6xz+12yz

=x²+4y²-4xy+9z²+12yz-6xz

=x²+4y²+9z²-2(2xy+3xz-6yz)