Hey I want to know what this type of function is called, why we are working out mi and Mi value, and how that connects to solving the problemAlso what does it mean to work out the lower and upper sum of (f + g, P) mean for solving the problemI am terribly lost :( any youtube vid on this would be greatly appreciatedAlso for some reason course MATA37 doesnt show up so i put it as MATA31 sorry

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