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zik
In session 7, he says "we just need one rate of change at one place, and then we work out all the rest of them". What exactly does he mean by this?
by knowing the bounderies/endpoits of the whole object in study ,then if we divide the object in to so many pieces .if we find the rate of change of one piece, we can by INTEGRATION .We integrate that piece in respect to the endpoints to find the rate of change of the whole object(other pieces)