Answer and explanation

Correct answer: C.

  1. Step 1: Write where is a perfect square.
  2. Step 2: .
Answer
.
Why not the others: is what you get if you keep the square factor under the root. is what you get if you swap the two numbers. is what you get if you multiply the root by .

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Simplify sqrt(72) in the… | GCE O/L Mathematics (Sri Lanka)