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Area under a curved graph

Let's explore how to calculate the area under a curved graph! Created by Vibhor Pandey.

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  • blobby green style avatar for user hin hin
    I don't get where was tf in the sigma notation :(
    (1 vote)
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    • blobby blue style avatar for user joshua
      t_f is the final time.

      To find the area under a curved graph, i.e. sum of v across the interval t_i to t_f, we integrate v.

      Let's take Worked example: Area below v-t graph as an example.

      A rabbit is trying to cross the road. Its velocity v as a function of time t is given in the graph, where rightwards is the positive velocity direction.

      At what time does the rabbit have the same position as t = 0?


      So now this problem is pretty easy.
      2
      ∫ v dt = total distance in positive direction = p
      0
      t_f in this case is the final endpoint time.

      x
      ∫ v dt = total distance in negative direction [2, x] = q
      2

      Now we just have to solve the equation for x.
      p = q

      If you are still unsure what am I doing, I strongly recommend you to check out AP Calculus AB or BC
      (1 vote)

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