Given the function FX = | X-1 | + | x-3 | (1), find the value range of X, make FX a constant function (2) if the inequality f about X The known function FX = | X-1 | + | x-3| (1) Find the value range of X so that FX is a constant function (2) If the inequality f (x) - a ≤ 0 about X has a solution, find the value range of real number a

Given the function FX = | X-1 | + | x-3 | (1), find the value range of X, make FX a constant function (2) if the inequality f about X The known function FX = | X-1 | + | x-3| (1) Find the value range of X so that FX is a constant function (2) If the inequality f (x) - a ≤ 0 about X has a solution, find the value range of real number a

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