The value of (a2/3 + 2a1/2 + 3a1/3 + 2a1/6 + 1)(a1/3 – 2a1/6 + 1) – a1/2 (a1/2 – 2), when a = 7 , is:
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e 1
| Application | Understanding |
| We need to convert them into a single form or try to make it into any format of any formula. |
The denominators of power of all are 1, 2,3 & 6 whose LCF is 6. Let a1 / 6 = t ⇒ (t4 + 2t3 + 3t2 + 2t + 1)(t2 – 2t + 1) – t3 (t3 – 2) ⇒ -2t5 + t4 + 2t5 - 4t4 +2t3 + 3t4 - 6t3 + 3t2 + 2t3 - 4t2 + 2t + t2 - 2t + 1 + 2t3 ⇒ 1 |