What is the value of ?
Answer and explanation
Correct answer: D.
- Step 1: Use the difference of two squares: with , .
- Step 2: and .
- Step 3: The product is .
Answer
.
Why not the others: is the sum ; is half of the correct difference and is double it; drops the surd.
Practise more Surds and indices.
Free questions with an explanation for every one, and full timed TMUA mock tests.