What are and ?
Also this is near impossible to read.
Are you asking to show this?
Prove that the following is true for all n ∈ N(natural numbers)
h^(n)= ∑ (k=0 to n) n!/k!(n-k)!f^(n-k) * g^(k)(x)
Note: We can assume Pascal’s Idenity for 1<(or=)k<(or=)m