Expand the following, using suitable identities:
(2x−y+z)2 [3 MARKS]
Formula: 1 Mark
Application: 2 Marks
(2x−y+z)2
Using the identity
(a+b+c)2=a2+b2+c2+2ab+2bc+2ca
a=2x,b=−y,c=z
=(2x)2+(−y)2+(z)2+2(2x)(−y)+2(−y)(z)+2(z)(2x)
=4x2+(y)2+(z)2−4xy−2yz+4xz