This problem does NOT ask you to "show that the function is twice differentiable". It asks you to show that "IF the function is twice differentiable ...".
Truncation of order 2?I do not understand how to do the question in part b.
Suppose I show that the function is twice differentiable (how do i do so), is that sufficient to show that the 'method' (does this refer to the prediction-correction method) has a truncation order of 2?
What is truncation?
Please see attached image.