Same" and "different" go hand in hand.
https://gyazo.com/e46356bad18de0658741b5cfc0492f0f
Another expression of rereading
It is easy to assume that "same" and "not match the correct (answer, etc.)" are incompatible, but this is because it is assumed that X and Y are a single point, and if both are set, a situation can arise where "the set is not equal, but is largely overlap' situation can occur if both are set. In that case, if you focus on the common part, they are 'the same', and if you focus on the rest, they are 'different'. When we say, "X is Y (the same as) Y," we are thinking "X=Y" if we consider X and Y as a single symbol.
However, if the assumption of a single point is incorrect,
If X or Y is a set
There could be a discrepancy between X and Y.
In that case, it is compatible for X to be (nearly) the same as Y and for there to be a difference between X and Y.
It is not "the same," but "the sets overlap significantly," or, to put it more softly, "[Similar.
2022-02-17 Changed title from "Same and different have the same root" to "Same and different are compatible"
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