Letf: [a,b] -> Rbe a real function

It is said thatfsatisfies the Holder condtion of orderalpha >0if there exists anM>0and sometilda>0such that for allx[0] in [a,b]and allx in [a,b] with 0<| x - x[0] | < tildait holds|f(x) - f(x[0]\ < M |x-x[0]|^alpha

iv already shown thatf:[a,b] -> Rsatisfies the Holder condition of orderaplha >0at anyx[0] in [a,b]whcih makesfcontinious

but now im stuck on the part where i want to show thatf:[a,b] -> Rsatisfies the Holder condition of ORDERaplha >1at anyx[0] in [a,b].thenfisdifferentiableat anyx[0] in [a,b].