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In searching for a suitable translation of 'indistinguishable', I found the French word 'indifférenciable'.

From my point of view, as an Anglophone, I wonder something when comparing this French word to English 'indifferentiable' (some would argue this isn't a word, but the colloquial meaning is "unable to differentiate"). I wonder if 'indifférenciable' also carries the meaning "Unable to to differentiate", not only in the sense of comparing differences, but also in the sense of derivatives and differentiation in the world of calculus.

My Question:

Can the word 'indifférenciable' imply 'unable to derive or differentiate' in the context of calculus?

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up vote 4 down vote accepted

In mathematics, we use non différentiable for non-differentiable functions just like we use non continue for non-continuous functions.

Indifférentiable has no definite mathematical meaning, it's only used for “impossible de trouver une différence” (very close to indistingable which means similarly “impossible à distinguer”), and it might apply to functions as well. “Deux fonctions non différentiables” and “deux fonctions indifférentiables” have different meanings.

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