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the heronian mean H(a,b) is defined as H(a,b)= (a + √ab +b)/3. what is the least positive integer b>40 such that H(40,b) is also a positive integer?

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Final answer:

To find the least positive integer b > 40 such that H(40,b) is also a positive integer, we need to eliminate the square root term by choosing a value for b that makes 40b a perfect square. The least positive integer b > 40 that makes 40b a perfect square is 49. Therefore, H(40,49) is a positive integer.

Step-by-step explanation:

To find the least positive integer b > 40 such that H(40,b) is also a positive integer, we can substitute the values into the given formula:

H(a,b) = (a + √ab + b)/3

By substituting a = 40, we get:

H(40,b) = (40 + √(40b) + b)/3

To find a positive integer b that makes H(40,b) a positive integer, we need to eliminate the square root term. This means that 40b must be a perfect square.

The least positive integer b > 40 that makes 40b a perfect square is 49.

Therefore, H(40,49) is a positive integer.

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