The first fraction divided by the second fraction is equivalent as multiplying the inverse of the second fraction
So the numerator in total will be: (a-4)(a+3)^2(a-1)
Denominator: 2(a^2 - a)(a-4) = 2a(a-1)(a-4)
Then, the same factor of numerator and denominator will be canceled out:
which are: (a-4)(a-1)
So the final answer:(a+3)^2 / 2a
