Quant Question Of The Day: 122
Numbers
For how many integer n, n2 + 10n + 2 is a perfect square?
For how many integer n, n2 + 10n + 2 is a perfect square?
Let n2+10n+ 2 = a2
(n+5)2-23=a2
(n+5)2– a2= 23
(n+5-a)(n+5+a)= 123
(n+5-a)(n+5+a)= 123
(n+5-a)(n+5+a)= -231
(n+5-a)(n+5+a)= -123
After solving we get two values of n= 7, n=-7
New Question: Coordinate Geometry
good information
By Những dòng bồn cầu thông minh ... , 1 month ago
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