2.8.70 Power Series

Condition: lay out the function \ (f (x) \) in a row according to degrees \ (\ left (x-x_ {0} \ right), \ quad \) using ready-made decays (i.e. not finding derivatives). At the same time, it is required to obtain an expression for a common member of a row and indicate an area in which the decomposition is fairly obtained. \ [3 x+\ sqrt {-\ frac {x} {2}}, \ quad X_ {0} =-1 \]