does anyone know this ?
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Answer:
Always
Step-by-step explanation:
If the irrational parts of the numbers have zero sum, the sum is rational. If not, the sum is irrational. It is true, for example, for 2 7, 3. It is false, for example, for3+2 5,−2 5 .
Answer:
always
Step-by-step explanation:
Rational numbers can be expressed as a fraction of two integers. So, adding two rationals is the same as adding two such fractions.