Yes. The rational numbers are a closed set with respect to subtraction.
Yes. This is the same as asking for one rational number to be subtracted from another; to do this each rational number is made into an equivalent rational number so that the two rational numbers have the same denominator, and then the numerators are subtracted which gives a rational number which may possibly be simplified.
The product of two rational numbers is always a rational number.
The product of two rational numbers is always a rational number.
Fractions where both the numerator and divisor are rational numbers are always rational numbers.
Yes, that's true.
Yes. The rational numbers are a closed set with respect to subtraction.
No. 5 and 2 are real numbers. Their difference, 3, is a rational number.
Yes. This is the same as asking for one rational number to be subtracted from another; to do this each rational number is made into an equivalent rational number so that the two rational numbers have the same denominator, and then the numerators are subtracted which gives a rational number which may possibly be simplified.
The product of two rational numbers is always a rational number.
The product of two rational numbers is always a rational number.
The difference of two rational numbers is rational. Let the two rational numbers be a/b and c/d, where a, b, c, and d are integers. Any rational number can be represented this way. Their difference is a/b-c/d = ad/bd-cb/bd = (ad-cb)/bd. Products and differences of integers are always integers. This means that ad-cb is an integer, and so is bd. Thus, (ad-cb)/bd is a rational number (since it is the ratio of two integers). This is equivalent to the difference of the original two rational numbers.
No, and I can prove it: -- The product of two rational numbers is always a rational number. -- If the two numbers happen to be the same number, then it's the square root of their product. -- Remember ... the product of two rational numbers is always a rational number. -- So the square of a rational number is always a rational number. -- So the square root of an irrational number can't be a rational number (because its square would be rational etc.).
Rational numbers are numbers that can be written as a fraction. Irrational numbers cannot be expressed as a fraction. All natural numbers are rational.
Yes.
Another rational number.
-- There's an infinite number of rational numbers. -- There's an infinite number of irrational numbers. -- There are more irrational numbers than rational numbers. -- The difference between the number of irrational numbers and the number of rational numbers is infinite.