Factorise:
a6+27b3
We know a3+b3=(a+b)(a2−ab+b2)a6+27b3=(a2)3−(3b)3=(a2+3b)((a2)2−3a2b+(3b)2)=(a2+3b)(a4−3a2b+9b2)
a6−b6
a6−7a3−8
a3−27b3+2a2b−6ab2