The given equation is
[tex] f(x) = a(x + 3)(x + 1)(x - 2)(x-3) [/tex]
It is given that , when x=0, f(x)=36
Substituting these values
[tex] 36 = a(0 + 3)(0 + 1)(0 - 2)(0-3) \\ 36 = a(3)(1)(-2)(-3) \\ 36 = 18a \\ a =2 [/tex]
So the missing value of a is 2 .