// (1) d which merely means “a little bit of.” Thus dx means a little bit of x (2) ∫ which is merely a long S, and may be called (if you like) “the sum of.” Thus ∫dx means the sum of all the little bits of x
// (1) d which merely means “a little bit of.” Thus dx means a little bit of x (2) ∫ which is merely a long S, and may be called (if you like) “the sum of.” Thus ∫dx means the sum of all the little bits of x
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