A square sheet of side cm has squares of side cut from its corners and the sides folded up to make an open box. What is the greatest possible volume?
Answer and explanation
Correct answer: B.
- Step 1: The box has base side and height , so .
- Step 2: , so (since gives zero volume).
- Step 3: .
Answer
.
Why not the others: : is the volume when , not the maximum. : is the area of the base at the best , not the volume. : doubles the correct maximum.
Practise more Differentiation.
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