How many integers x satisfy x^2 < 7x?
x2 is the same as x • x so since (x • x) must be less than (7 • x) then x has to be less than 7..
The interval 0 < x < 7 contains 6 integers that comply with this requirement, namely 1, 2, 3, 4, 5, and 6.
You can't use negative integers because then x2 would be positive, thus larger than 7x which would be negative.
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