elly4964 elly4964
  • 16-09-2018
  • Mathematics
contestada

Prove that if xy > 0, then either x > 0 and y > 0 or x < 0 and y < 0

Respuesta :

Аноним Аноним
  • 16-09-2018

The rule of product states that:

  • [tex] (+) \cdot (+) = (+) [/tex]
  • [tex] (+) \cdot (-) = (-) [/tex]
  • [tex] (-) \cdot (+) = (-) [/tex]
  • [tex] (-) \cdot (-) = (+) [/tex]

So, a product is positive if and only if both factors have the same sign, and is negative if only if the factors have opposite sign.

Answer Link

Otras preguntas

how to determine if values are significantly different
Solve the triangle. Round your answers to the nearest tenth.
Which of the following falls outside of the classification of business expenditures that fall into the category of variable costs? a) costs that increase with t
Write one difference between national heritage and world heritage.​
m A math teacher gives a quiz. Each question on the quiz is worth 8 points. A score of 75 is a passing grade. Which number of correct answers will result in a p
Which of the following is most likely the final stage of the business buying decision process
Yolanda paid for her movie ticket using 28 coins, all nickels and quarters. the ticket cost $4. which system of linear equations can be used to find the number
If you suggest that smiling can make someone feel happier, then you are relying on the:
A nurse is caring for a patient prescribed tPa for a stroke. What actions by the nurse are most appropriate
What conclusions can we draw from trait theory