Big Ideas Math Integrated I, 2016
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Big Ideas Math Integrated I, 2016 View details
2. Inductive and Deductive Reasoning
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Exercise 13 Page 456

If we call the numbers a and b, we can write two inequalities describing the conjecture.

See solution.

Practice makes perfect

We want to find a counterexample that proves the given conjecture false. If we call the numbers a and b, we can write the conjecture mathematically as two inequalities. ab&>a ab&>bIf we solve for b and a in these inequalities, we get two intervals describing a and b. ab/a&>a/a ⇔ b>1 [1em] ab/b&> b/b ⇔ a>1 As we can see, both a and b have to be greater than 1 in order for the inequalities to hold true. Therefore, by setting one of the numbers equal to or less than 1, we have found a counterexample. 1( 5)= 5 Since 5 is equal to one of the numbers in our product, we have found a counterexample that proves the conjecture is false.