The base of a solid is the region in the first quadrant bounded by , the -axis, and the -axis. Cross sections perpendicular to the -axis are squares. Find the volume of the solid.

Answer and explanation

Correct answer: A.

  1. Step 1: Cross sections perpendicular to the -axis have side length .
  2. Step 2: The area of each square cross section is .
  3. Step 3: The region extends from to (where ).
  4. Step 4: Integrate: .
  5. Step 5: Evaluate at limits: .
Answer
.
Why not the others: '1/3' computes ; '2/3' integrates ; '4/15' halves the true volume.

Practise more Integration.

Free questions with an explanation for every one, and full timed AP (Advanced Placement) mock tests.