Do you mean ? If so, we may differentiate it as follows:
Use L'hospital's Rule to evaluate
Lim x -->0 9x(cos5x-1)/sin(2x-2x)
I know that this is a 0/0 indeterminate form and you need to differentiable both top and bottom until you can substitute 0 into x. I have problems differentiating sin(2x-2x).