How do you graph f(x) = x - [[x]]
Well that will depend upon what "[[x]]" means! If it is the "floor" function, you should be able to calculate a few values at, say 0.5, 0.7, 0.9, 1.2, 1.4, 1.7, 2.5. 2.7, 2.9 and see for your self.
Do you see that [[x]] is same as [x]? Plotting f(x) should be trivial once you notice that.
(assuming [x] denotes the floor function)
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