Maths-
General
Easy
Question
The sum of two numbers is 20. If the product of the square of one number and cube of the other is maximum, then the numbers are
- 12, 8
- 3, 4
- 9, 12
- 15, 18
The correct answer is: 12, 8
Let the numbers be 

Let 

For maximum or minimum, put 

or 
cannot be 0 or 20
Now 
For
and 
is maximum at 
For
, then 
The required numbers are 12, 8
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