Question

expand the following expression (x-2y+3z)square

Answer 1

Use this  (a- b + c ) ^2 = a2 + b2 + c2                                     -2ab - 2bc +2ca

Answer 2

$x^{2}$-4xy+6xz+$4y^{2}$-12yz+$9z^{2}$