Question

The set of integral values of m for which line x + y = m cuts hyperbola xy = 1 at integral points-

• A. {1, –1}
• B. {­–2, 2}
• C. Null set
• D. None of these

Answer 1

Answer: (B)

{­–2, 2}

Answer 2

x + y = m; x y = 1

on the curve xy =1

we have two integral points (1, 1) & (–1, –1)

These points will lie on the line x +y = m

Ž m = ± 2