JAMB Mathematics 2011 Question 8

Question 8

Surds

Rationalize (2 − √5)/(3 − √5).

  1. A.(1 − √5)/2
  2. B.(1 − √5)/4
  3. C.(√5 − 1)/2
  4. D.(1 + √5)/4
Show the answer and explanation

Answer: B ((1 − √5)/4)

Explanation

Multiply by (3 + √5)/(3 + √5): (6 + 2√5 − 3√5 − 5)/(9 − 5) = (1 − √5)/4.