Which statement is not always true?
The sum of a rational number and an irrational number is irrational.
The sum of two rational numbers is rational.
The product of two irrational numbers is irrational.
The product of two rational numbers is rational.
The statement "The sum of a rational number and an irrational number is irrational" is not always true.
This is because there are cases where the sum of a rational number and an irrational number can be rational. For example, if we consider the rational number 1 and the irrational number √2, their sum is 1 + √2 which is irrational. However, if we consider the rational number 1 and the irrational number -√2, their sum is 1 + (-√2) = 1 - √2 which is rational.