Write the Following in Expanded Form
\[ (-3x + y + z)^2 \]
Solution:
Using identity:
\[ (a+b+c)^2 = a^2+b^2+c^2+2ab+2bc+2ca \]
\[ (-3x + y + z)^2 \]
\[ = (-3x)^2 + y^2 + z^2 + 2(-3x)(y) + 2(y)(z) + 2(z)(-3x) \]
\[ = 9x^2 + y^2 + z^2 – 6xy + 2yz – 6xz \]