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algebra intermediate

Problem

How many integers satisfy the inequality ?
Solution
Distributing the left side of the inequality, we have , which simplifies to . This can be factored into , and we can now look at the three regions formed by this inequality: and . We know that the signs in each of these regions alternate, and we test any number in each of the regions to make sure. Plugging into , any less than yields a positive product, and any greater than also yields a positive product. The remaining interval between and inclusive yields a nonpositive product. Thus, there are integers which satisfy the inequality: , and .
Final answer
3