Which ONE of the following rules of differentiation is NOT correct?
Select one:
O a. If f(2)=zm, then f'(z) = mz^(−1)
○ b. If ƒ(z) = a + bz^(2), then ƒ'(z) = a + 2bmz^(1)
O c. If f(z) = g(z) + h(z), then f'(z) = g'(z) + h'(z).
O d. If f(z) = a, then ƒ'(z) = 0.