Engineering Board Exam Reviewer · Applications: Centroid, Work, and Moment of Inertia · medium

Find the y-coordinate of the centroid of the region bounded by y=4-x2 and the x-axis.

  1. 8/5
  2. 4/5
  3. 16/15
  4. 2

Answer

A. 8/5

Solution

A= -22(4-x2)dx=32/3. y= 1A -22 12(4-x2)2dx=3/32·256/15= 85.

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