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=== First-order methods ===
First-order methods assume that ''f'' is continuously differentiable, and that we can evaluate not only ''f'' but also its derivative.<ref name=":0" />{{Rp|location=sec.5}}

* The [[bisection method]] computes the derivative of ''f'' at the center of the interval, ''c'': if f'(c)=0, then this is the minimum point; if f'(''c'')>0, then the minimum must be in [''a'',''c'']; if f'(''c'')<0, then the minimum must be in [''c'',''z'']. This method has linear convergence with rate 0.5.