MODERATE EXERCISES - Basic Rules of Algebra

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Using the basic rules BR1 - BR12, show that the following properties of real numbers also hold:

(1) 1 + 1 0 ( Click On SOLUTION To See The Answer )

(2) If a > 0, then ¹/_a > 0. ( SOLUTION )

(3) If a > 0 and b > c then ab > ac. ( SOLUTION )

(4) If a < 0 and b > c, then ab < ac. ( SOLUTION )

(5) Expand or FOIL: (2x + 5)(x + 7) ( SOLUTION )

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