Multiple choice

Expand and simplify (2 + √5)(3 - √5)

  1. 1 + √5

  2. 11 + √5

  3. 1 - √5

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A Correct answer
Explanation

Expanding (2 + sqrt(5))(3 - sqrt(5)) using FOIL: 2*3 - 2*sqrt(5) + 3*sqrt(5) - (sqrt(5))^2 = 6 + sqrt(5) - 5 = 1 + sqrt(5).