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Given that is irrational, the number is:

Class 10Real NumbersNumber Systems
  • ARational
  • BEqual to zero
  • CIrrational
  • DNon-terminating recurring

Step-by-Step Solution

Suppose were rational. Then would be rational minus rational, i.e. rational — contradicting that is irrational. So the number is irrational. "Non-terminating recurring" is wrong because recurring decimals are exactly the RATIONAL numbers.
Answer: C) Irrational

Key idea: Sum/product of rational and irrational

**Useful results**:

1. The sum or difference of a rational and an irrational is IRRATIONAL.
Proof: if (rational + irrational) = rational, then irrational = rational − rational = rational. Contradiction.

2. The product of a NON-ZERO rational and an irrational is IRRATIONAL.

3. The sum/product of two irrationals can be RATIONAL or IRRATIONAL.
Example: (irrational); (rational).
Example: (rational); (irrational).

These are the rules you cite when proving expressions like ' is irrational'.

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