[n^1/2 ] = 17

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[n^1/2 ] = 17

by sanju09 » Tue Mar 03, 2009 4:27 am
[x] is the greatest integer less than or equal to the real number x. How many natural numbers n satisfy the equation [n^1/2 ] = 17?
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by DanaJ » Tue Mar 03, 2009 4:36 am
The problem can be translated into:
17 <= n^1/2 < 18
289 <= n < 324
There are 324 - 289 = 24 + 11 = 35 numbers that satisfy this equation.
This type of function is used in conjunction with {x} or the fractional part of x (meaning stuff that's after the "." for positive numbers)