Answer
$11x(x^2+y)(x^2-y)$
Work Step by Step
The product of a binomial sum and a binomial difference is: $(A+B)(A-B)=A^2-B^2$.
The square of a binomial sum is: $(A+B)^2=A^2+2AB+B^2$.
The square of a binomial difference is: $(A-B)^2=A^2-2AB+B^2$.
Hence here: $11x^5-11xy^2=\\=11x(x^4-y^2)\\=11x((x^2)^2-y^2)\\=11x(x^2+y)(x^2-y)$