Question

write (2x - y+z )^2 in explained form

Answer 1

$using \: (a + b + c)^{2} = {a}^{2} + {b}^{2} + {c}^{2} + 2(ab + bc + ca) \\ \\ (2x - y + z) ^{2} \\ \\ = ({2x})^{2} + ( - y) ^{2} + {z}^{2} + 2(2x)( - y) + 2( - y)z + 2z(2x) \\ = 4 {x}^{2} + {y}^{2} + {z}^{2} - 4xy - 2yz+ 4xz$