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Let $a$ be the acceleration, $v_i$ the initial velocity, $v_f$ the final velocity, $v(t)$ the velocity at time $t$, $d$ the distance, $T_s$ the switch time and $T_f$ the final (stopping) time. Then it is easily seen that

$$d=-\frac{a}{2}(T_f^2 - 4T_fT_s + 2Ts^2)+ T_f v_i,\quad v(T_f)=v_i+2aT_s-aT_f=v_f.$$

This is a system of two equations and two unknowns, whose solution is

$$ T_s=\frac{2v_i+\sqrt{4ad+2(v_i^2+v_f^2)}}{2a},\quad T_f=\frac{v_i+v_f+\sqrt{4ad+2(v_i^2+v_f^2)}}{a}. $$