Factorise: (x+2)3−(x−2)3
(x+2)3–(x–2)3=(x+2−x+2)((x+2)2+(x−2)2+(x2−4))=4(x2+4+4x+x2+4−4x+x2−4)=4(3x2+4)
Factorise: (x+2)3+(x−2)3
(x+2)3+(x−2)3