2016 · Q3
What is (6² + 7² + 8² + 9² + 10²) / [√(7 + 4√3) − √(4 + 2√3)] equal to?
Elementary MathematicsNumber System
- A330
- B340
- C355
- D366
Explanation
Numerator: 36+49+64+81+100 = 330. Denominator: √(7+4√3) = √((2+√3)²) = 2+√3, and √(4+2√3) = √((√3+1)²) = √3+1. Their difference is (2+√3)−(√3+1) = 1. So the fraction equals 330/1 = 330 (option A).