SOLUTION: The sum of the first n integers 1+2+3+...+n=n(n+1)/2 a.How many numbers must be taken to have a sum greater than one million? b.Why can the sum never equal 1000000?

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Question 1146603: The sum of the first n integers 1+2+3+...+n=n(n+1)/2
a.How many numbers must be taken to have a sum greater than one million?
b.Why can the sum never equal 1000000?

Answer by math_helper(2461)   (Show Source): You can put this solution on YOUR website!

a) n(n+1)/2 > 1000000
n(n+1) > 2000000

Solve for n, n >= 1414

b) n(n+1)/2 = 1000000
n(n+1) = 2000000 has no integer solutions


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