a, b, and x are positive integers such that
How many possible values of x less than or equal to 1000 are there?
This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try
refreshing the page, (b) enabling javascript if it is disabled on your browser and,
finally, (c)
loading the
non-javascript version of this page
. We're sorry about the hassle.
This is solvable if and only if x has a perfect square factor. Proof:
x = a + b + 2 a b so a b must be a square. So if a has an odd powered factor then b has the same odd powered factor.
a simplifies to a number of form d ∗ c , this implies b simplifies to e ∗ c therefore
x = d ∗ c + e ∗ c = ( d + e ) ∗ c
x = ( d + e ) 2 ∗ c
so x has a perfect square factor.
Counting the number of integers to 1000 which have a square factor takes awhile but is trivial. There are 3 9 2 of them.