It is always FALSE.
Yes
Yes. For example, if you multiply the square root of 2 (an irrational number) by itself, the answer is 2 (a rational number). The golden ratio (Phi, approx. 1.618) multiplied by (1/Phi) (both irrational numbers) equals 1 (rational). However, this is not necessarily true for all irrational numbers.
That simply isn't true. The sum of two irrational numbers CAN BE rational, but it can also be irrational. As an example, the square root of 2 plus the square root of 2 is irrational.
This can't be proved because it is not necessarily true. If x is 2 and y is 1 then x-y is 1, which is rational. The product of 2x and 3y is 12, which is also rational. Sadly, you can't disprove it either; for certain values of x,y it is true as posited.
Yes, that's true.
It is always true.
The product of 2 rationals must be rational. The product of a rational and an irrational is irrational (unless the rational is 0) The product of two irrationals can be either rational or irrational.
It is true.
Yes
Yes. For example, if you multiply the square root of 2 (an irrational number) by itself, the answer is 2 (a rational number). The golden ratio (Phi, approx. 1.618) multiplied by (1/Phi) (both irrational numbers) equals 1 (rational). However, this is not necessarily true for all irrational numbers.
True.
In between any two rational numbers there is an irrational number. In between any two irrational numbers there is a rational number.
In between any two rational numbers there is an irrational number. In between any two Irrational Numbers there is a rational number.
That simply isn't true. The sum of two irrational numbers CAN BE rational, but it can also be irrational. As an example, the square root of 2 plus the square root of 2 is irrational.
Any and every rational number.
Only if the negative sign is associated with an even root. In that case, the number is neither rational nor irrational, but is imaginary.
yes