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Show that the following statement is true.p: For any real numbers x, y if x = y, then 2x + a = 2y + a when a ∈ Z. - Mathematics

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Question

Show that the following statement is true.
p: For any real numbers x, y if x = y, then 2x + a = 2y + a when a ∈ Z.

Sum
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Solution

We prove the statement ‘p’ is true by contrapositive method and by Direct Method.

Direct Method for any real number x, y given

x = y

⇒ 2x = 2y

⇒ 2x + a = 2y + a for some a ∈ Z.

Contrapositive Method The contrapositive statement of ‘p’ is

“For any real numbers x, y if 2x + a ≠ 2y + a

Where a ∈ Z, then x ≠ y.

Given 2x + a ≠ 2y + a

⇒ 2x ≠ 2y

⇒ x ≠ y

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Chapter 14: Mathematical Reasoning - Solved Examples [Page 260]

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NCERT Exemplar Mathematics [English] Class 11
Chapter 14 Mathematical Reasoning
Solved Examples | Q 14 | Page 260

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