-(-x^2y)^3×[(xy)^(n+1)]^2
=(x^2y)^3*(xy)^(2n+2)
=x^6y^3*x^(2n+3)y^(2n+1)
=x^(6+2n+3)*y^(3+2n+1)
=x^(2n+9)*y^(2n+4).