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Printsmc
counting and probability intermediate
Problem
For how many integers between 1 and 100 does factor into the product of two linear factors with integer coefficients?
(A)
(B)
(C)
(D)
Solution
For to factor into a product of two linear factors, we must have , where and are integers. By expansion of the product of the linear factors and comparison to the original quadratic, . The only way for this to work if is a positive integer is if . Here are the possible pairs: This gives us 9 integers for , .
Final answer
D