Answer :
[tex]64x^3+y^3=(4x)^3+y^3\\\\=(4x+y)[(4x)^2-4xy+y^2]=(4x+y)(16x^2-4xy+y^2)[/tex]
[tex]a^3+b^3=(a+b)(a^2-ab+b^2)\\-----------------\\64x^3+y^3=(4x)^3+y^3=(4x+y)[(4x)^2-4x\cdot y+y^2]=\\\\=(4x+y)(16x^2-4xy+y^2)[/tex]
