resolution(_a, _b, _c, _x1, _x2) :- _delta is _b * _b - 4 * _a * _c, resolution(_a, _b, _c, _delta, _x1, _x2). resolution(_a, _b, _c, _delta, _x1, _x2) :- inf(_delta, 0, true), write("no solution"). resolution(_a, _b, _c, 0, _x1, _x2) :- _x1 is (_b / 2 * _a). ///////////////////////////// ERREUR si on ecrit _x1 is -(_b / 2 * _a). resolution(_a, _b, _c, _delta, "-b -", "-b +"). inf(_x, _y, _z) :- _z is _x < _y.