Question

(b) "If x > 0 and y > 0 then xy > 0" where x,y are real numbers.

Answer 1

Explanation:

We know that multiplication product of two given positive real number will always be positive real number and if one of the real number is negative, the multiplication product will always be negative.

so for the given condition, if
`x > 0` and
`y > 0`,
`x` and
`y` are both positive real numbers

hence their multiplication product
`xy` will also be a positive number.

∴
`xy > 0`