Expand and simplify .
Answer and explanation
Correct answer: B.
- Step 1: Difference of two squares: .
- Step 2: .
Answer
.
Why not the others: is what you get if you add instead of subtract. is what you get if you square the difference. is what you get if you square the surd as .
Practise more Indices, Logarithms and Surds.
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