Tannenberg is the German name for the formerly East Prussian, now Polish, city of Olsztynek[?]. It is still widely known by its German name due to two famous battles fought in its vicinity, in 1410 and 1914.
... then there is a repeated solution x, and this solution is real. (Geometrically, this means that the parabola described by the quadratic equation touches the x-axis in a ...