Factorise fully .
Answer and explanation
Correct answer: A.
- Step 1: Take out the common factor 3: .
- Step 2: Recognise .
- Step 3: So the full factorisation is .
Answer
.
Why not the others: : treats the difference of squares as a perfect square. : is not fully factorised because still has a common factor of 3. : does not multiply back to .
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